I just randomly thought of how funny it would be if Piplup evolved without any warning. It'll never happen, of course, but it would be hilarious to see everyone's reactions since we're all so sure it will stay a Piplup forever, what with it being the D/P mascot.
Also remembered that Happiny evolving would mean Brock would need a new baby to occupy himself with. I like Brock being the one given all the babies, so I want to see that continue if the current baby grows up. Probably a 5th generation pre-evolution, since I can't think of any already-known Pokémon that would really work.
That brings up the question, exactly how soon after 5th gens start being revealed can we expect the twerps and Rockets to add them to their line-ups? Or we going to wait for a possible post-Sinnoh arc or are we going to have another Munchlax situation?