UFC was/is the primal reason behind WWE's ongoing(has been for a long time already) decline. Obviously, I would expect people to guess where the WWE fans went to.
Boxing only. The Sweet Science RULES, always has, and always will. UFC is okay when they actually throw some punches and engage in ACTION. But when they're rolling around on the ground, it's just DULL.
I watch both; boxing live and MMA from torrents later. Way more boxing minded but MMA has more fighters I look forward to see.
MMA has plateaued if you ask me.... It was growing rapidly because it was a new sport, but it's definitely been stagnant for the last few years, even a bit stale.