Also, I think that the LT team had said that they couldn't achieve as much feedback as they wanted to without developing a new language (that I'm guessing is a bit more progressive than Swift) in order to allow for a more interactive experience.
So, with no insider info, I'm guessing that if they hadn't started developing their own language they may have been leapfrogged, but given that they don't really have to language design constraints around Cocoa/Objective-C semantics maybe they are still pretty far ahead. The harder part is getting enough programmers to care, even if they come out with something really revolutionary.