I keep revisiting this subject, from time to time. This weekend I was almost convinced I had to buy an ereader. Now I've changed my mind again, after a little bit of research.
Item the first: I really like the Sony reader. It's small, comes in a nice case, and you can get it in red! Red is the best color! But you have to buy books from the Sony store exclusively, or suffer with smallified (un-zoomable) PDF versions of text. Also, there's no internet connection; you plug it into your computer to load it, like my cheap-ass MP3 player. So you can't buy and download a book on impulse.
Item the second: the Kindle is hideous, badly designed with too many buttons, and you have to pay to transfer PDFs onto it. It has internet capability, but an oppressive EULA.
Item the third: $400 for a Kindle, $300 for a Sony reader, and then around $10 for each book.
Here's an excellent article about ebooks and readers and how people think of them at Ars Technica (I got it via Making Light). Essentially, the article's point is that ebooks are inevitable and the resistance people have to them right now is illogical, but that adoption of ebooks is hampered by DRM and confusion about ereaders and downloads (and a lot of other stuff).
Back about (gosh!) a year and a half ago, when I was first thinking of ebooks and wondering what I wanted in one, I said I wanted one that would mimic a book in certain ways--opening up with two screens in the middle (like facing pages) and so forth. I don't think that's necessary now. What I want in an ereader is the ability to download on the fly from anywhere. If I want to buy a book in PDF form directly from a small publisher, I want to be able to do that. If I want to buy a book from Sony's store, or Amazon's Kindle store, I want to be able to do that too and read it. In short, I don't want to have to deal with DRM, or proprietary software crap, or restrictions on internet access. Slap a wifi connection in my reader and let's go!
Oh, and I want to pay about $100 for my reader, and about $5 each for my books. I think that's reasonable. And if this $100 reader and these $5 books perform the way I envision, the ebook/reader market will blossom like a rose garden in June. Someone's going to get filthy rich when they figure it all out. I wish they'd hurry.