Hardware
I'm going to touch on hardware first, as that's a reasonably good introduction to the device. First! Some specs:
Processor: Intel Atom @ 1.66 GHz
RAM: 2GB DDR3
HD: 16 GB Solid state drive
Screen: 1280x800
Graphics: integrated
So keep in mind that this device is not the biggest powerhouse on the block. The casing itself though feels quite spiffy, the matte rubber coating on it feels great, and the mouse pad is almost as good as my Macbook Pro's.
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The device is quite small, 12", completely dwarfed by my 23" monitor in the background
ChromeOS
The idea behind the operating system is to live completely on "the cloud", this magical location somehow made up of Internet, and honestly, I don't think Google could have timed it better. At this point, most of us are getting pretty used to doing things online, especially with the rise of Facebook as a platform for so much of our social data, and Dropbox for storing our files across multiple computers. What I'm trying to say is that living on the cloud completely isn't all that far-fetched.
Good things
I just want to say, the way I work on my computers in general has already changed, even after only a mere few weeks. I find myself relying far more on web based applications, especially for quick or simple tasks. It's hard to beat the convenience of having your workspace in a web tab, right next to your research information, and the site you're going to put your work on. I've also spent a fair bit more time on Google Docs, which really is quite delightful, especially with all of their recent changes.
If you've used Chrome on your desktop computer, you should have a collection of bookmarks, web apps, settings, and user preference data, and if you've set it up right, that data should be associated with your Google account. All of that data gets transfered over to the ChromeOS, and is constantly synced between whatever devices you have running chrome. Not having to worry about transferring data between computers allows the ChromeOS to fall perfectly into a support role for your main computer.
The interface to the OS is incredibly simple, and rather intuitive. It literally is almost exclusively your web browser. If you've used Chrome, you've already seen the interface. If you haven't, then you should, Chrome is a great browser =D The OS also has some pop-up tabs for things such as a download browser and gTalk windows, which are incredibly convenient, and rather unobtrusive.
One of my biggest apprehensions about using ChromeOS was not being able to code. I'm a coder, and I can't do without it. But I quickly found that it's not that hard to do web development online. There are plenty of web based web development tools, and even a few web based compilers that will compile applications in a wide range of different languages(Ideone is pretty nice). They might have to lean a little on the simple side, console windows, fixed input and the like, but it's definitely a start. Just the other day, I found myself writing code in a web window on my main computer, even though I had a couple copies of Visual Studio up in the background. I was pretty surprised.
Also, Teminal window! (Ctrl + Alt + t)
Bad things
Lets start with some simple things, like renaming files. While working on the cloud is great and all, files will eventually end up on your computer in some fashion or another, whether it be uploading pictures from SD card, or downloading from Google Docs to upload back into a class file submission, you still need to work with files. I'm OK with that, and they do have a file browser and all that fun stuff, but you can't rename files. Pretty simple, but important.
Chrome allows for multiple windows, each with multiple tabs. I think its pretty great, but each of these windows is fullscreen, so there's no way to drag tabs between windows. It would be nice to be able to right click on a tab and say 'move over one window' or some such. Google also doesn't do the standard alt+tab that Windows does, it merely rotates through, rather than switching between the most important windows first. There's a reason why Microsoft does it the way they do, and Google should pay attention in this case.
Plugins! Flash is built in, that's cool... but the web runs on more than Flash these days! For example, Silverlight. ChromeOS is built on top of Linux, and there is a Linux plugin for Silverlight out there. ChromeOS can't install or run it though. Same goes for Java, doesn't work. That's a bit of a big problem.
HURG @.@ THIS THING IS SLOW. Can't play video well, can't play games without lag... I hate integrated graphics chips... General use is quite fine otherwise. (Gawker doesn't count anymore, they just screwed up)
Also, Terminal window was nerfed :'(
Conclusion
Overall, I rather like the ChromeOS, and I really believe it's the future. The problems that I've pointed out so far are small details easily fixed by a quick patch, and the good parts really shine through to make the experience quite great. I'm not ditching my Windows 7 yet though we've still got a long ways to go... but it sure does make a great support computer in the meantime!