It appears that the closed beta for Realtime Worlds' APB is underway, according to reports over at Eurogamer and Kotaku. A number of applicants have apparently received their invites, and are reporting that test days are currently Tuesday, Thursday, and Sunday from 7-11PM with the first hour of testing focused solely on the game's "Social District."
If you've not applied for the APB beta, you can still do so here.
Via Eurogamer.