Something cool to note about Whimsicott: it gives Rain teams yet ANOTHER weapon to use, since:
252SpAtk Life Orb Whimsicott (+SAtk) Hurricane vs 252HP/0SpDef Amoonguss (Neutral): 73% - 86% (316 - 374 HP). Guaranteed 2HKO.
252SpAtk Life Orb Infiltrator Whimsicott (+SAtk) Hurricane vs 252HP/252SpDef Leftovers Ludicolo (+SpDef): 51% - 62% (188 - 226 HP). Guaranteed 2HKO.
It also completely replaces Jumpluff on Sunny Day teams but that's another point. Given that Scolipede is dropping too, Spikes will be extremely easy to get up (as they were in round 0), since you can sash Scolipede and get up 2 layers off the bat if you really need to, or force switches as Scolipede is the first spiker since, well, Scolipede, with an actual offensive presence.
Speaking of Scolipede it's going to immediately jump to the top 5 in usage. The only spinner able to touch it in NU is Torkoal really, since Hitmonchan can only spin away the Spikes and not actually take care of the mon itself. I doubt SD/BP sets will be used in general; they weren't really that effective. However, I could be wrong since you're losing three Pokemon that give Scolipede fits (Cincinno is still around though :<) Spikes/Tspikes are really too good to pass up, as evidenced by people using Whirlipede and Glalie and stuff.