'Model not registered' loading regression in Django 1.7

C&P from an email:

I think a change to get_model for Django 1.7 might be in order. It currently uses get_registered_model, which we decided on because it doesn't choke if the registry is still being populated. But there's a regression: if a model has indeed not been loaded just because the application import process hasn't run over it, then it now fails where it didn't use to fail before. 
I'm not entirely sure what the right fix is. All other calls to load models would choke on the app registry not being ready. But we need a way to attempt to load the models in the specified app before we fail with a LookupError.

Hat tip to @metamatik for spotting the issue.