Anyone already running 2.2.0 Build 894 should see a dialog prompting them to get new installers next time they launch Architect.

Build 908 fixes a variety of issues. Learn more here:

http://docs.sencha.com/architect/2/#!/guide/whats_new

and here:

http://docs.sencha.com/architect/2/#!/guide/changelog

We have not yet turned on auto-update notification for Architect 2.1 users, that should be coming soon.