Looks like Gmail has switched up their interface a little bit: Here is the Old: Here is the New: Notice the new "Move to" and "Labels" buttons witch I believe use to be in the "More Actions" section
I wonder if that update was causing the issues this morning. Gmail was being super wonky for a while there - kind of annoying to have your email interrupted for such a minor change. Of course, I shouldn't complain given how infrequently we see any changes to Gmail