I'm thrilled about this expansion. Ignoring all the content changes, some of the things that interest me particularly from a multiboxing standpoint:

1. Level 85 (not 90)
2. Rated battlegrounds instead of arena
3. No talent tree extensions (please, no more 61 point one trick pony gimmick talents)

I think those 3 things alone are enough to get any pvp multiboxer excited.