I'm with Natch on this one.
Right now, I'm lucky enough to have a 505 and certainly appreciate the updated firmware. But when I bought the 505, I bought it for what it could do out of the box, not with any future expectations.
I have been caught in the no upgrades for your device with my Apple iPod, and I'm still a loyal iPod user. I just know that I can't take advantage of all the neat features that owners of newer iPods can. Still, my iPod hasn't lost any features--it still does everything it did when I purchased it. And I've gotten plenty of use out of it.
Unless something better comes along (more features I'm interested in, etc), I'll probably buy another iPod or another Sony reader when my current ones die.
dordale