Yesterday in a comment regarding the post about Zondervan's partnership with Sony Reader, someone asked how the Kindle and Sony compares. Here's some info I've gathered.
Mark and I have a Kindle. (Actually it's his--Christmas present last year.) We love it. Easy to read, easy to turn pages. Great for loading manuscripts! For example, once I finish a book I can email the manuscript to his Kindle email account, and he can read it on the Kindle rather than carrying around a bunch of pages. I hear many agents and editors are using this feature now, as the Kindle also allows you to highlight passages and make notes on the pages. Not sure the Sony Reader allows highlighting or note-taking. I've heard one report that it doesn't.
Another big difference between the two is that the Kindle doesn't need a PC to transfer content to it. The Sony Reader does (and it's not MAC compatible). Let's say you're in an airport and see a new hardback for sale for $25. With your Kindle you can get online and order the book--and have it within 30 seconds--for under $10. (Assuming it's available; many new titles are going directly to Kindle.) The Kindle also allows some web browsing and has a dictionary.
With the Kindle you can subscribe to online newspapers daily or get it just for one day. Let's say you're traveling and miss your daily hit of the Wall Street Journal. You could buy a hard copy, but newspaper reading is hard on an airplane. On the Kindle you could download the day's issue in seconds. If you have a regular subscription, the minute you turn on your Kindle, the day's issue is there.
As a pure e-reader, the Sony is a little smaller and lighter, I hear. And it's cheaper.
Problem is, my knowledge is limited (and unfair) because I don't have a Sony Reader. So below are links to thoughtful analyses and comparisons of the two:
Gizmodo comparison 1
Gizmodo comparison 2
Mid-day update: In today's comments someone has said that the Sony IS now Mac compatible.