I like the 505 because it's very good for reading books - I don't care so much about connectivity. The ability to buy books from the device is handy, but it's not the be-all and end-all. As far as I'm concerned the biggest thing about the new Sony with wireless is that it allows a defense against the "But it doesn't have wireless" crowd.
A thief, a warrior, a wizard, two warring prophecies; they all come together in Amadar. Available now on Amazon
; coming soon to Smashwords and others.