I think they're using Git. But this would clearly be awesome... (And an alternative to full github access).
One easy way to do this would be to create a public repo sencha-touch-nightly on your github, and then with a daily Cron -> git pull YourCurrentRepoOrigin --force ;git push ThePublicRepoRemote --force.
Oh pleaaaase ! I'm stuck on PR-1 like... Forever !!!
We were hoping for a PR3 release this week, but fixing bugs and finishing off existing components that are not complete is the top priority us. I'm hoping for an release early next week, but don't hold me to that (as always).
Sencha Inc. Robert Dougan - @rdougan
Sencha Touch 2 and Ext JS 4 Core Team Member, SASS/Theming Wizard.