Wired has a decent review of the Kindle 2. It's quite favorable though the author points out that it has no chance of becoming the ipod of ebook readers.
http://www.wired.com/reviews/product/kindle2
I would say that the reasons why it won't become universally popular is rather simple: it doesn't sell outside the USA. On top of this, the ebooks are still too expensive in the eyes of consumers to justify the switch.
Slowly the market is ripening for a major player to sweep it entirely and take all the glory. We'll see what happens in the next 3 years. It should be interesting.
Competition is good!