The one that'll really stir the pot is XTR Di2. I can hear the angst already

In other areas, I think some of the changes are overdue, if anything. Axle standards that were carried over from road bikes are a good example. In this day of 5"-6" bikes, it's about time we had steertubes, axles, hubs and forks that were actually built with their function in mind, rather than backwards compatibility. The tipping point has just about been reached.

The pressfit BB standards look like a win-win. Easier and cheaper to manufacture, wider bearing support for the crankset, more room to attach frame tubes, and there's at least some cross-adaptability among some standards.

Direct-mount FDs, I'm lukewarm on that one. It makes things simpler for the factory worker, it allows unconventional frame designs... but sometimes it's nice to be able to angle the FD cage relative to the chainrings just a hair.