I purchased the Barnes & Noble Nook several months ago, and like most people here, I find it mostly useful, but I don't think it will completely replace hardbacks. (Paperbacks, maybe, but not a good, quality hardback edition of any of your favorites.) Also, to clarify, I read lots of novels, and some non-fiction, mainly history related and current events, and sometimes biographies or humorous works. I never intended to use an eReader as a way to carry a lot of reference works around, and after seeing how they work, I'm not entirely sure that this is better than pdf's on a laptop. I did install a thesaurus, but found that the edition I purchased isn't what I imagined it would be. Searching is slow and awkward, and although the backbone of ePub files is XHTML, this thesaurus was surprisingly link-free. I would have thought that linking words upon words would be the prime reason to have a thesaurus as an ebook.
Here's what I don't like:
The Nook has had some hardware issues which I had to contend with and overcome. (I've had to shim the battery in its holder so that it made good contact with the electrodes, and two of the paging buttons are cracked -- although the unit still works fine. By all accounts, B&N will exchange mine no questions asked; I just haven't gotten around to it.) However, even with these issues, I'm still happy with it and have no regrets.
Page turning was a little slow at first, but a software revision fixed that.
The Barnes & Noble book browsing experience is nowhere near as helpful as the Amazon website experience is. I find myself browsing at the Amazon site, then buying the books I find on my Nook. The Barnes & Noble book browsing experience is pretty much limited to searching through lists beginning with the best sellers. If you're happy with reading those, you'll quickly find reading material. If you prefer reading off-the-beaten path works, browsing for books really sucks. Otherwise, you have to know what authors you want to search for, as it is unlikely you'll make any serendipitous finds.
Maybe it's because I'm an old school gal, but reading with the Nook is just not the same as curling up with a good book. It is by no means bad, but it doesn't feel quite the same, either. (Although, this could be an old-dog/new-tricks problem.)
On airplanes, during take-off and landing, you have to turn these off. You don't have to do that with a paper book.
I don't necessarily mind re-purchasing some of my favorite books, but the medium is still too young to have extensive back-lists available for many of my favorite mid-list authors. I scanned one paperback that I desperately wanted an e-version for, and went through the conversion (from pdf scan to text) and re-conversion (from text to ePub) and successfully got it on the Nook. Whew! It took a lot of work, and I would gladly have paid for the convenience of not having to go through all that. To be fair, though, this isn't a problem specific to the Nook; it exists with all eReaders to varying degrees.
Remembering to recharge a battery can be a challenge for me. (This challenge is paradoxically easier AND harder when faced with re-charging all my other electronics. I have SO many things that need re-charging that it reminds me to add the Nook to the list, but....I have SOOO many things that need re-charging that I feel overwhelmed!)
You still need an external light to read by. This is not usually a problem, as most of the time one is available, but it is something to consider.
It cannot replace picture books or art books. The screen is monochrome.
What I Like:
It's perfect for travel. I travel a fair bit, and sometimes to some pretty out-of-the-way, rural places. I used to try and pack enough reading material, but the weight of all that was a constant nuisance. That's no longer an issue.
It's especially nice to be able to subscribe to one of the major newspapers using my Nook. When I'm traveling in rural Alabama or Arkansas, I am at least assured that I'll have a newspaper to read, which makes me feel in touch with the rest of the world. Even at home, it's nice to not have to run to the newstand to buy my daily copy, nor do I have the bother of recycling the piles of newsprint every week. I hope more magazines will also come on board; that would be far more convenient than searching high and low for a newstand that carries obscure journals.
It conveniently fits in my purse, or my bag, and is always available whenever I find myself waiting in line, or at a restaurant. And it remembers exactly where I left off reading; no more fumbling for something to use as a bookmark.
As many others have pointed out, the classics are all freely available from sites like Project Gutenberg. You can, if you wish, buy them, too, and for only $1 or $2 dollars you can get them downloaded without hooking it up to a computer and downloading and sideloading the work. (You pay for convenience, in this case.) Even some early to mid 20th century works are available at low cost. For example, Winston Churchill's History of the English Speaking Peoples is available at $4 per volume, which for me is low enough to consider buying one to see what it's like. I've always wanted to try this work, but didn't ever want to pay full paper edition prices for something I might find uninvolving. (Yeah, yeah, there's the library for that, too....)
I like being able to change fonts (the Nook has 3 available) and to re-size the fonts.
The Nook gets two small essays downloaded every morning. One is a humorous piece, and the other is a related to literature. While I wouldn't make my purchasing decision on this feature alone, it is a nice touch.
I like the user interface, which is a combination of a color touch screen and buttons for turning pages. I found it pretty intuitive to figure out, and haven't had to resort to any user's manual yet.
I like being able to buy books via 3G. Yes, the B&N book browsing experience leaves much to be desired, but even so, if you're not near a bookstore, and you've run out of fresh reading material, it's still pretty awesome.
I have sooo many books, that I've started to have to prune my collection. An ebook edition is a painless way to still have some of your favorites on hand -- especially if like me, you like to reread them a lot.
Things I Don't Care About One Way Or Another:
Lending books. My tastes are so different than most that no one bothers with what I read, and it's rare for anyone to have what I like on their shelves. While I think it's a shame that digital editions are so locked up that one cannot lend something to a friend, the way you can with a paper edition, it hasn't proven to be any special hardship for me.
The Nook has a couple of games on it that you can play. One is chess, the other is sodoku wordgames. I don't do either of these. (But if they ever get freecell, or mah-jong, look out baby!!)
The Nook also has a web browser, but it isn't especially fast. (It's still in Beta.) I have used it, but with the grayscale screen, most color websites aren't all that easy to read, and one has to use the touchscreen for scrolling, which makes it awkward to navigate websites. Still, in a pinch, you can use this to catch up with a favorite blog -- assuming you can find a wifi access point.