Just about an hour ago, a VVVVVV update was pushed out through Steam!
Now the executables are there! \o/
My only sorrow is that it still has the V2.0 executable... Any hope that V2.1 comes through as well?
Anyway, the Steam Linux version of VVVVVV uses the same save files as the non-Steam Linux version (~/.vvvvvv/). That wouldn't be a problem if they weren't of different versions. V2.0 nicely reset my "disable OpenGL" setting, for example - I hope it didn't corrupt anything else.