On build 2157, I got a dead lock while doing a "find usages" action on a C# member in a WPF project. Files were scanned and the progression dialog stopped on a XAML file. I tried to cancel the action but cancelling didn't work either. I previously had this same kind of deadlocks on previous builds but never had the time to take a snapshop. Now I did, and one CPU core is fully used on what seems to be a SpinWaitLock.
You'll find on your FTP a full memory dump of Visual Studio during the dead lock. The file is named ReSharper 2157 Find Usages DeadLock XAML Lebosquain.7z