As with every update Niantic releases for Pokemon GO, dataminers have been pouring through the data to glean info on what's coming next. The latest update includes some interesting tidbits, with mention of Generation III Pokemon catching a lot of attention. 135 Pokemon from Gen III have been spotted, but they don't have any sound data tied to them. If they are indeed on the way, it might be some time before we see them.
Also found hiding in the most recent update was an item called the Super Incubator. The only detail we know right now is that it's purple in color. No word on when or how you'll be able to obtain it.