First the good stuff:
The "free sample" feature is fantastic! I have ordered many, many samples of books. About 75 percent of the time I said, "eh" and didn't buy them. But they were all books I would never have bought without "tasting" first, so I bought more books because of this feature, not less.
The screen is easy on my eyes, and every book is a large print book when needed. Amazingly, I have recently noticed large print editions listed on the Kindle store. I got a free sample to check them out, and it seems like the only difference is the behavior of the "default" font size (3 of 6). When you open the book with the font size set to 3, you get size 6, but it doesn't get any larger (that I could see, anyway) if you then change it to size 6.
I can hold the Kindle and turn the page with one hand (this took practice, but I'm there).
I can easily buy short fiction by authors I like, if they have their work on Fictionwise.
Buying books is so easy!
Here's what I don't like:
Buying books is so easy! Yes, I know I listed that under what I like, but I have to say, this thing could be dangerous for a book addict.
Sorting: Although I can filter out newspaper and magazines, I can't sort books except by title, author, and date last read. I'd really like to be able to apply a genre label, and see only books in a specific genre.
Book formatting: this is the big one. Even in books I have paid for (although not usually more than $3.50), I have seen really bad formatting glitches. In S.J. Rozan's Reflecting the Sky the starting quote marks for dialog often appear somewhere above where they should be—as in two or three lines above. Very annoying! In the Kindle edition of Rebel Spurs ($2.39 from Optal eBooks) by Andre Norton, that I bought all the characters with special accent marks (tildes, acutes, etc.) come out totally weird and virtually unreadable. It turns out there is in fact a more expensive Kindle edition ($4.79 from Oak Grove) in which the formatting is much better. I should also note the original paperback is out of print and I've never seen it for less than $30.00, although there is a reprinted edition out there. If I had done the free sample thing, I might have noticed the bad formatting in the cheaper version, depending on where the sample broke off, but I might not. In any event, it is annoying that folks are posting these editions on the Kindle store and not checking the quality of the formatting. Sheesh!