I purchased the S205 recently as I wanted an ultra mobile laptop with reasonable performance that I could take on the road with me without being overly restricted by size or battery life constraints.
Basically the S205 is a netbook and a beautiful one at that, and with a computing platform this small you've got to be realistic about the performance you expect from it. "Good enough" computing is what the S205 is all about it does its job. Don't expect it to be as quick as a Core I3 based laptop or some of the Llano mobile devices.
First of all I'll discuss what I think about this laptop then I'll go through the individual components of the S205 with what I like and don't like

Small.
Performs very well for web browsing and Youtube.
Handles High def video fine and connects to 1080P TV via HDMI output (cable not included).
Not a games machine so forget it if you are looking to play modern games like Battlefield 3. However it does handle games from 3-4 years ago very well and casual games like Plants Vs Zombies run fine.
Doesn't get hot at all, therefore comfortable when used for extended periods on my knees.
Quiet- little heat therefore fans don't need to run at high speed.
Battery lasts for ages.

Keyboard: I'm not that demanding with regard to this aspect of a device but I found it an excellent keyboard with a nice feel and I enjoyed typing on it. The keyboard does sit at a slight angle as the battery raises the base of the laptop up slightly to generate a slight incline. This may or may not be to an individual's preference but I liked it. The purpose of this incline is meant to be for providing a better typing experience but I reckon it's also to allow a bigger battery to be fitted inside the case.

Touchpad: Seems as good as any I've used however I pretty much hate them all.

Screen: Nice enough when viewed straight on but don't expect wide viewing angles on a laptop this small. It does its job but not fantastic.

Hard Drive: Think mines is a Western Digital model and scores 5.9 in Windows Experience Index which is fairly decent. Like any 2.5" mechanical hard drive it doesn't seem lightning quick but it's reasonable. 500GB is an excellent amount of storage though on a device this size.

Operating System: As described in the product description it is Home Premium 64 bit. I was pretty impressed with this as previous S205 models had only used the 32 bit version. The benefits of the 64 bit version are better performance, better memory management and it's supposed to be more secure according to Microsoft. The downside is you need a minimum of 4GB to see decent performance but fortunately that's provided.

Processor/Graphics: The S205 uses AMD's Brazos APU and this year Lenovo have used the new E450 version rather than last years E350. Having never used a PC with the E350 I don't have a frame of reference with which to compare it. A 50MHz processor clock speed increase for each of the 2 processing core is probably not going to be that noticeable. However the graphics core (HD6320) can turbo up to 600MHz now which is a fair bit of headroom over the old E350s (HD6310) so should help with more demanding graphical applications. My experience is that it runs Windows Media Center effortlessly and I tried Prey Prey (PC DVD)(a game from 3-4 years back) and it ran smoothly on high settings. Word processing, Excel etc all work extremely well. I can say that performance is much better than Atom based netbooks I've used. Processor scores 3.9 on Windows Experience Index, not high enough for heavy work but that's the price you pay for small size, low heat and noise and great battery life.

Ethernet: No Gigabit ethernet only 10/100Mb. Disappointing but not a deal breaker and Wireless N in theory has a greater bandwidth. Since I'm using the S205 as a mobile device I doubt I'll ever be relying on the wired ethernet port on a daily basis anyway so not a big issue.

Wifi: I never seem to get the max number of bars suggesting wireless strength isn't that great, however I've connected to my wireless N router and browsed the internet when being 30 feet away through two brick walls so it seems decent enough.
Update 1/1/12 Wifi performance will vary depending on whether you are connected to the mains or running from battery. Power profiles in Windows,AMD Catalyst Driver and Lenovo Energy management can reduce performance of the Wifi in order to conserve the battery. Everything is user definable and you can create your own plans if you desire to allow max Wifi performance on battery if you desire. To keep things simple I uninstalled the Lenovo Energy Management software, the AMD Catalyst driver (accessible from the Start Menu or the toolbar at the bottom... Read more

I have reviewed two previous models of this netbook earlier this year, and both were the best in class at a time, but this one got even better.

It has the same amount of memory (4GB) and 500GB HD as previous model, but this is more than enough for a small travel-size netbook. No need to upgrade, and also this is quite tricky on Lenovo netbooks (you need to remove keaboard etc). What is different for this model is the new updated AMD processor - E450 vs E350. It has slightly higher CPU clock rate (1.65GHz vs 1.60Ghz) and 508GHz GPU but due to extra turbo-core it can go up to 600MHz, which gives 20-30% increase in games and benchmarks. Overall this CPU/GPU combination is very powerful, most games are absolutely playable, HD Video running smoothly, and normal tasks like Web browsing, emails, office documents editing performed very fast. In fact Word starts almost instantly, in less than 1 second. Overall PC startup time is less than a minute inc login which is pretty impresive for Windows netbook. I attach a large 23" monitor to in in the office and this little beast manages 2 screens perfectly, second in 1950x1050 HD resolution.

Considering it's still the size/price of a typical (good) netbook we are talking here it's just amazing. In fact the specs of this machine are better than of my desktop (which is not new I admit).

The build quality is exceptional, with sleek design, quality almost full-size keyboard (I think letter keys are full-size, they only fiddled with arrows and enter buttons). Keyboard is the best around - I tried dozens of note/netbooks at PC World and other shops to compare (as I am using it for a lot of typing). Even more expensive models like Sony VAIO have inferior keyboards. Trackpad could be larger but it's OK. Glossy cover is a finger-print magnet (it is very hard to find matte cover on a netbook) but thanks to patterned design it's not so visible. Go off easily as well.

I was a bit conserned about glossy display but in fact it's not so bad - brighter than matte display and not so much reflective. Colours and contrast are very punchy, good for video/tv watching. Now having used it for some time I am not sure I would swap it for a matte screen. Much easier to clean as well.

It comes with Windows 7 Premium 64bit installed, which is much better than Starter edition, and you can upgrade memory up to 8GB, which will boost performance even further (if you really want to). Not too many extra software installed which is good, as most got deleted right away.

The only thing I'd want to improve is to split C drive in 2. Currently everything is on C (there is 20GB D drive but it is used for recovery system) so if you will have to re-install Windows or use the recovery utility you will lose all your data - backups are essential for this netbook! You can create a new drive of course but it will stop the recovery utility from working. Surely Lenovo could have designed this better.

Battery life is so good I forgot to mention it, as I almost never go flat. 6-cell gives you 5+ hours of normal work time (browsing, email, documents, etc). Obviously games/videos will take more juice.

All in all I think it is a perfect on-the-road netebook, light, stylish, with great battery life, and exceptionally fast. Very happy with it. I can only see myself replacing it with another netbook with even better processor (maybe ARM when they will run Windows 8) but that won't happen for good 2 years I think.

Strongly recommend, and these 5 stars come from a very demanding user.

All in all this is a nice little machine. It runs well, boots in about 60 seconds (faster than most netbooks I've seen/used in the past), and is a nice size for working on. It has plenty of ports on the side including 3 USB 2.0 ports, HDMI + DVI out, and an Ethernet port. (Has mic and headphone port but I can't comment because I haven't used either). It's keyboard is a useable size however takes some getting used to if you're used to a fullsize keyboard or a large laptop, but has many useful Function keys and all the normal keys of a full size (bar a keypad of course)

However, the main problem of this Laptop is the wireless network strength. I understand the majority of the time you'd be using a netbook is out and about for work or with a mobile dongle so to some this wouldn't be a big deal, although using it at home with a wireless router is nothing short of painful. I seems to have trouble connecting through anything more than 2/3 walls, and I get about 3/4 bars sitting 3 feet from the router itself.
Saying this, I've converted to using an ethernet cable and it downloads at about 30mbps (70 mbps connection, so this suggests that the network card just isn't up to scratch) which is adequate for a netbook such as this

all in all, if you're planning to use this away from home, it is your best bet. Slighty bigger and more powerful than the average netbook its a nice little runner thats sure to serve you well for a long while. However, if for whatever reason you're planning to use this at home permanently (?) go for something else, because the connection issues are sure to irritate you eventually