Patch 1.1 states that the crash during multiplayer has been identified and fixed, and the servers should now have implemented the fix.
However, I am still getting random freeze during multiplayer. My game does not crash into windows, but instead the screen and sound would freeze. Sometimes it only freeze for 2-3 seconds, and the game would resume. But most of the time, it would continue to freeze, and my only solution is to Ctrl+Alt+Del and End Task.
My system is:
Intel i5 2500K @ 3.3GHz
ATI Radeon HD6970 by Sapphire
16Gb G.Skill RipJaw DDR3 1866 RAM
ASUS V8Z68-V Pro motherboard
HT Omega Striker soundcard