That's a great price! I already have a 505 that I got at Fry's for $250 and I thought that was a deal.
FWIW I have both the 505 and Kindle 2. (Gave away my Kindle 1 to my mother in law). They each have their merits. I really like the Amazon store and downloading paid for books via whispernet. I also think the Kindle 2 interface is better designed and more elegant.
But for books that I download or scan or convert from other formats, I find that I generally prefer the 505.
Also, I kind of get sick of having every book I read look the same. Switching readers enhances the experience.