Well, not really a review. More of an initial reaction. I received a NOOKcolor as a Christmas gift. As did my oldest daughter. My two younger kids both received the regular Nook.
I've downloaded a couple of books to the Nook and turned a few pages in, but didn't actually start reading any of them to read them - just to see how it looked and how it worked. One neat thing about the Nook is that you can put any .pdf or open ePub format book on it to read. You're not restricted to buying books from Barnes & Noble.
My local library (as I'm sure many others do) have an ebook check-out option using Adobe Digital Editions. You download the book from the library to your home computer, then hook up your Nook to that computer and transfer the file over to the Nook. After two weeks or however long the library has it set up, your rental of that book expires and you no longer have access to it unless you check it out again. There are also thousands of free ebooks available from various sources, including the Barnes & Noble website and Project Gutenberg.
The NOOKcolor is basically just a branded, locked-down tablet PC running on the Android operating system. It comes with a built-in web browser, and yes, you can surf the internet with this ereader - which is what I've mostly used it for the past few days. It has a touchscreen for navigation and control, as well as a software keyboard almost exactly like a smartphone. As you can add your own ebooks onto the optional sd card, you can also add videos and watch them or music files - but they have to be formatted a specific way and size. You'll need to Google the exact settings to get it right.
A nitpick: it seems you need to turn it off and back on sometimes after making changes or additions to get it to sync up, not after adding books but after adding other stuff. After adding videos, I didn't get any sound. Rebooting the unit made it work fine.
The NOOKcolor has a single built-in speaker, but includes a standard stereo headphone jack. You can watch movies or listen to music, or even listen to audiobooks using it. The unit itself isn't heavy, nor is it too light. It seems the perfect weight.
A few other tidbits: like smartphones and other tablets the screen auto-rotates to match how you're holding the unit, which makes browsing the internet and watching videos a nicer experience. You can get a variety of covers/cases for your Nook, some with pockets and some without. These serve to protect your Nook, and make it look snazzy. And like other Android devices, you can "root" it to gain more control over the operating system and use more Android apps on it than what Barnes & Noble intended. Also, unlike other devices, the Nook does not charge when plugged into your USB port on your computer. It only charges via the AC adapter.
I mentioned putting ePub files on the Nook. There's a program called Calibre that will convert ebooks from one file type to another for use with your Nook, or other ereader. It can convert .pdf, .doc, .txt, and many other formats. Another source for free ebooks is Baen. In fact, they often include a CD full of ebooks in their hardback releases. That's kind of awesome in my opinion!
There's much more to this little device, I haven't had much time to actually play with it and get into the thick of it (let alone actually read something on it...). All in all, I'm quite pleased with the NOOKcolor and look forward to using it more.