MG is definitely progressing much faster since it seems to be much more actively developed lately, but GAE still has a lot of exclusive features like attack effects, transports, water travel, and others, and also has a great new interface. Once MG implements all of those things, I would call it "caught up", and GAE would be basically obsolete. Hopefully that would more a matter of adapting GAE code to work with MG rather than reinventing the wheel, so to speak. I've been a fan of GAE for years, but I would gladly switch if that happened.