Mekkah: that one turn of set-up is found easily when the opponent's first reaction is to switch in a Poke such as Weezing, Zapdos, Slowbro, Celebi, Gyarados, Cresselia, (or other Pokes which do well to what people believe to be the Bulk Up Set). And once you've reached 502 SAtk, it's not like you're running a gimmick set or something. You must have missed it in my post, I mentioned Togekiss (and I'll add in Yanmega too now) can take the NP set.
Besides, my point wasn't that NP > Bulk Up, just that between the two you have hardly no common counters, and imo you should be prepared for both as the NP I posted is not just a gimmick set. For other Pokes whose place in OU is questioned by some, (this pretty much only applies to Garchomp, but I think many of you would would agree Revenankh is on that level) at least their counters are always the same Pokes.
Okay, I kind of see a flaw in my argument, that you could compare the NP set to Chain Chomp. I guess we'll just have to wait some more and see if it catches on, but theory-wise to me I don't see why it wouldn't.
Aldaron: Sure, there is some good to come out of using Pokes from BL to counter Revenankh, in that it diversifies the game. But it's not so much the Pokemon as the moves and specific sets you have to use on them (Metal Sound Zapdos, CM Cresselia and Celebi) which, while they might be good sets in their own right, are too specific. Is using a CM Psychic Cresselia over a standard physical wall version, or Metal Sound Zapdos over those more Bulky versions, all just for Revenankh, really something your team can handle with everything else in OU? I'm gonna make another comparison to Garchomp which I think is more fitting. The most common counter to the most feared Pokemon in OU is Ice Beam, but using Ice Beam isn't ony preparing you against Garchomp. Pretty much all Dragons, as well as a few other Pokes are brought down by this move. Sure, CM Cresselia was around before Revenankh was still great, and now there's even better reason to use it. But really for the majority of Revenankh's counters, you're being forced to run a particular set in order to counter him.
And someone please explain to me how Leech Seed alone is a counter to Bulk Up Revenankh. I mean, you just use Bulk Up with care and calculate carefully when you'll have to use Rest, and you should be able to take out the Leech Seeder with 3-4 Bulk Ups.