I played a bit in my personal home instance and I was still very choppy there, not as choppy as when there were 30 people, but still very bad. I gave my account intel to a friend, so he can at least enjoy the game for a bit. I'm not going to play during this weekend anymore.
I'd be interested in knowing people's specs.
I have a fairly lag-free experience, plus framerates that don't dip below 20 even in crowds (which is my threshold before it starts getting annoying).
My system is a couple years old too:
Core i5 760 (quad core) overclocked to 3.3 Ghz
GTX 450 OC
8GB G.Skill performance ram
Win 7 64-bit
What are you guys running?