570
AOSP isn't dead, but Google just landed a huge blow to custom ROM developers
(www.androidauthority.com)
This is a most excellent place for technology news and articles.
There are some 7-8" tablets that could probably fit in a pocket, but finding the perfect mix of Linux compatibility and cell chip is going to be difficult.
However, I see a few Linux tablets out there that have to be all runs, because Linux tablets are a pretty small niche, so it might not be that expensive to build one yourself.