This isn't really important and I don't see it being of too much note however, I just noticed that Air Lock (Rayquaza's ability) now has a notification of activation when he is sent out, kinda like Pressure.
Minor change, but a change all the same.
EDIT: Air Lock having a warning doesn't change much, as Rayquaza does not have an alternate ability. Cloud Nine, however, also displays a warning. Several new pokemon got this ability and it looks as though using it to bluff will not be possible.
@Reaverz: So far Air Lock doesn't erase ability-induced weather. At least not Drizzle from Kyogre. Weather icon is still on the bottom screen (there is no in-between turns animation anymore). I'll test same situation w/Cloud Nine and then move onto TM Weather and T-Tar/etc.
Progress:
-Cloud Nine and Airlock both do not erase Drizzle, Sandstream. (Opponent Activated)
-Cloud Nine and Airlock did not erase Rain Dance, Hail, or Sunny Day. (I activated these ones)
I'm going to assume that they work in the same manner as before, only now with an activation message when being sent out.