Just in case you're interested, there is a Nidoqueen Suspect discussion @ smogon. What do you guys think of Nidoqueen? Should it be banned?
In my opinion, Nidoqueen can be quite versatile - as a special attacker, as a physical attacker, and as a physical sponge. Nidoqueen itself already gives a lot of slower teams a lot of issues. Whenever I use Nidoqueen, I use her to destroy walls such as Tangrowth, Steelix, and other excellent Pokemon who counter much of the metagame are incredibly difficult to use with Nidoqueen around, as since they are slower and risk being OHKO'd by Nidoqueen, and Nidoqueen forces them into a lethal guessing game, that Nidoqueen has a significant advantage in.
So, maybe Nidoqueen might of had enough of an impact to the RU metagame that stall teams would have significant trouble against a Nidoqueen? Perhaps it might be a suspect because of that impact?