I always used the 770 with the OEM OS2006; it was rock solid and never had a limitation on web browsing.
but the n800 gave me the web-cam, a crappy fm radio and a faster cpu....
so what ?
I can tell you it was not a good reason as OS2008 is not A LOT better than OS2006 when you use the tablet as is for video-mp3-web
My call : keep the 770+OS2006 until the n810 can be found at a better price; unless you are a youtube or web2.0 freak