I knew the faction imbalance was going to be bad, but I didn't think it would be utterly fucked. I really had no desire in going republic, but I'm having second thoughts now. Even though every class is 100% mirrored, empire's are just so much more interesting, to me at least.
edit: Also, Wound In the Force is apparently going to be "the" PvP server. West coast at least.
The Swiftsure is the unofficial oceanic server.
For east coast, Veela seems to be one of the few (if only?) PvP servers that actually has more republic guilds on it. Also, Kinrath Spider seems like it'll be good too - apparently a lot of the good swg guilds are rolling there.