I have been experiencing the same problem for the last week or two. I decided to try to track down the problem tonight and narrowed it down to VIEmu. If I disable it I have no problems. If I enable VIEmu then VS crashes when I close it. I was about to start a thread on this problem when I discovered WorldMaker.
This is kind of a pain in the neck. Sometimes I have three instances of VS running and then when I want to shut everything down, they all three crash and automatically restart. If I don't edit any files then I can shut them down without them restarting.
All I have to do to get VS to crash on shutdown is to open a solution and insert some text and save the file. Then shutdown VS and it crashes.
I have ReSharper 7.0 installed. This does not seem to have an impact but I thought I would mention that I do have it.
Here is the log from my Event Viewer for the crash. I don't see it as too helpful but it is the best that I can provide.
I hope you can figure this one out quickly as it is a bit of a pain. Let me know if you want me to try anything to help track the problem down.
Faulting application name: devenv.exe, version: 11.0.50727.1, time stamp: 0x5011ecaa
Faulting module name: ntdll.dll, version: 6.1.7600.16915, time stamp: 0x4ec49d10
Exception code: 0xc0000374
Fault offset: 0x000ce903
Faulting process id: 0x1b58
Faulting application start time: 0x01cd7c3415a7cd80
Faulting application path: C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\devenv.exe
Faulting module path: C:\Windows\SysWOW64\ntdll.dll
Report Id: f247a120-e827-11e1-8d5b-545b3b9ecd0d