I was able to accomplish this by writing a custom `TestClassExtensionAttribute` and then calling a custom `ITestMethodInvoker` from the `TestExtensionExecution`.

I answered a similar question on SO about this: 
http://stackoverflow.com/a/14673329/573218

I have posted the code on GitHub and am working on cleaning it up a bit:
https://github.com/johnkoerner/MSTestLooper