I almost forgot.  There's a new exchange being created in the US by the dev of P$, AMK, and GOD.  He and some other people are putting it together because they are sick of all the bullshit exchanges out there.  I can't remember what it will be called, but I'll look it up.  I can ask them when they get it up.  Also, Atomic Trade seems to be another possibility, as they are quite reputable, albeit smaller.