I got my Nexus today and input those APN's. 3G/web access is working pretty good, but i'm not able to send MMS messages. I did some google searching and found some other info, but nothing that's working so far. I put in epc.tmobile.com for "MMSC"
How about the other fields: MMS proxy, MCC, and MNC?
By the way, i'm using the tmobile shadow web.