I, like many of you, just bought a 505 a little over a month ago. Also like many of you, I was relatively confident in thinking that Sony wasn't going to release a new model since they have been promoting the heck out of the 505.
However, I'm not at all disappointed with my 505 purchase (quite the contrary), and after reading about the 700, I'm not going to be upgrading.
Here are my concerns about the 700 (and keep in mind, some of these things are difficult to speculate on, given that I haven't actually had the chance to see/try a 700 in person):
1. What is the integrated frontlight going to do to battery life?
As it stands, I have the 505 with the integrated cover/lightwedge, I'm very happy with it's performance, and it doesn't effect the battery life of my reader. And I can't wait to hear someone's real world test of the light...one review already claims it's not bright enough for reading in total darkness, which I do a lot.
2. The missing page turn buttons on the right.
The way I'm used to holding my reader has me turning the pages almost exclusively with the right side buttons. They're perfectly placed under my thumb, and it looks as though utilizing the 2nd and 3rd buttons from the left on the bottom of the 700 would be awkward for me. But it has a touchscreen, you say....see my next point.
3. The touchscreen.
I don't really see the utility of this (speaking only for myself, you understand). Pressing a few buttons isn't the bane of my existence. And as I've mentioned in other threads, the performance of PlasticLogic's eInk touchscreen makes me nervous, and I hope Sony has improved upon it...it looked a little flaky (slow to respond, not very sensitive). Also, I know that my touchscreen would look like heck very soon after purchase...smudgy, dirty, scratched, etc.
4. The aesthetic.
I'm an equal opportunity criticizer...some of you may remember my thoughts on the Kindle. Well, I don't think the 700 is as bad as the Kindle, but I don't love it..and I'm usually a big fan of Sony's designs. To me, it looks like a step backward...and what's with those crazy textured lines along the left hand side? Just odd looking, I think.
5. The added features.
While some folks will get a lot of use out of things like search, annotating, and highlighting, I wouldn't really utilize those features...even if the 505 had them. So for me, they aren't a selling point.
6. The price.
I do think that for a first time reader buyer, the 700 might be a wise choice at the price point Sony has chosen. However, as someone who would be upgrading, I simply can't justify the $100 increase for what amounts to (for me, anyway) just an integrated light.
So I'll continue to love all over my 505, at least until something substantively better comes along!