I'm going for Shazzrah, simply because everyone I know personally is going there. There isn't even a specific reason I guess it just spread as the "place to be" for people in my area. There were a few wanting to swap to Gehennas after Blizz announced they were going to add it, however the majority of us have already reserved our characters so it's too late now!
Orc Warlock - Shazzrah (EU) - PVP