I've added a screenshot of a partial mockup I whipped together, running on my Galaxy Tab:
https://www.mediawiki.org/wiki/Mobile_mockups_for_Android_style#Mockup_for_t... (the second pic is the new one)
This is proposing using tabs to select between 'search', 'nearby', 'saved', and 'history' as navigation options for the left bar, and puts some key things on the action bar as clickable options (read in..., save, and share page), plus the overflow menu. I was too lazy to replicate the proper overflow menu icon so it's showing a settings icon. ;)
Not fully working version is in git, my 'tabs' branch: https://github.com/brion/Wikipedia/commits/tabs
A fair amount of basic tablet-style layout is already landed in master though, as additional CSS and a couple JS tweaks. The Android automatic builds should include a tweak to a sidebar / main two-column layout on large screens, but none of the fancy menus yet.
-- brion