Raikou, Zapdos countering Vaporeon

probably just hasn't been updated yet.

The list probably hasn't been updated yet because not every region has had access to Raikou. I imagine the lists will be updated after the final rotation.

I was about to ask this same question. Hopefully Gamepress will answer, but I think the answer is that Gamepress has just not got around to doing it yet. There is no good reason for Gamepress to wait until all regions have access to Raikou to include Raikou in its rankings. Gamepress has included the "regionals" in its rankings before. I assume the failure of Gamepress to include Raikou is just because it has to prioritize its work. That said, maybe the real question should be the one that I am about to ask. Please see the Q&As after this post.