On an official Microsoft announcement today we found about five new arcade in addition to the already announced Geometry Wars: Retro Evolved 2.

Here are the official dates:

Geometry Wars: Retro Evolved 2 – July 30
Braid – August 6
Bionic Commando: Rearmed – August 13 (confirms the rumor I posted earlier on the website)
Galaga Legions – August 20
Castle Crashers – August 27

In addition, every time you play a trial game or full version of these games of the week, you will earn one entry into the Summer of Arcade sweepstakes, with a chance to win one of the following prizes:

Grand Prize (x1) – 100,000 Microsoft Points, 12 month Xbox LIVE Gold subscription and an Xbox 360 Elite console
Runner-Up Prizes (x2) – 10,000 Microsoft points and a free 12 Month Xbox LIVE Gold subscription
Weekly Prizes (x5) – 4000 Microsoft points

Looks like a fun summer for XBLA subscribers!