At this point, the beta will be taken offline so that Blizzard can "make some hardware and software configuration changes in preparation for the final phase of the beta test and the release of the game."
A second phase will run "for a couple of weeks prior to the game's launch," which is set for July 27 worldwide.
Blizzard has historically run open "stress tests" prior to its game releases, but it is unknown if this second beta phase will be open.
Phase 1: Closed Beta
Phase 2: ???
Phase 3: Profit