Update: You can fix Xcode 7β3 "open project crash" by opening Xcode 6, going to preferences, "Accounts" tab, and removing repositories on the left.
Xcode 7β3 crashes when I open a project or try to create one...
Application Specific Information:
ProductBuildVersion: 7A152u
ASSERTION FAILURE in /Library/Caches/com.apple.xbs/Sources/IDEFrameworks/IDEFrameworks-8163.8/IDEFoundation/SourceControl/Model/IDESourceControlTree.m:82
Details: (location) should not be nil.
Object: <IDESourceControlRepository: 0x7fafccd67880>
Method: -_initWithLocation:sourceControlManager:
Thread: <NSThread: 0x7fafc943cbf0>{number = 1, name = main}
Hints: None
Tweets: