The 770 is a marginally better e-book reader (i.e. FBReader platform) than the N800, but the web browser is (by all accounts) significantly better on the N800. So the N800 is probably your best bet, unless the next version
, perhaps due soon, is a significant advance. It will have a built-in (slider) hardware keyboard, which I find very useful on my Pepper Pad 3 for the low volume typing typical of web browsing. Many web sites really require 800 pixel wide screens, so I would not go for anything less than that.
At one time I thought that Intel MID's would be available this year, and be real competitors to the N800 (e.g. relatively inexpensive and running full-blown Firefox). But it now looks like most (perhaps all) won't be available until next year, and ARM is fighting back (with Nokia leading the charge).