Something I haven't seen mentioned here is Baton Pass. With nigh-invincibility in Magic Bounce, Baton Pass teams have become even better in BW. I built a team that wasn't too different from ipl's and was able to ladder quite well with it. I won't say it's broken, but it is quite easy to win against unprepared players. With this in mind, should Baton Pass become more popular, I believe certain movesets may become more popular. One in particular would be Taunt Tyranitar. It's a very nifty Pokemon to use against Baton Pass teams since its powerful attacks can threaten almost every member of a Baton Pass team. A moveset consisting of Taunt, Crunch, Stone Edge, and Roar or Fire Blast (maybe Dragon Tail) demolishes my team, for example. Taunt prohibits them from passing any boosts, and since it directly threatens the two most crucial members of a typical Baton Pass team, Espeon and Ninjask, it's basically a free 6-0. Thundurus is also a major problem to some Baton Pass teams since it can Nasty Plot or Taunt while they try and switch around. Additionally, Special Defense is usually the last stat a team will attempt to boost, often opting to let Espeon itself Calm Mind, so if you can get Thundurus in early, the opponent will definitely have a tough time defeating it.
p.s. - is the smogon server down; i can't log on