For those of you having issues the MMS functionality after upgrading to the newer radios, check out this thread over at xda-developers.
http://forum.xda-developers.com/showthread.php?t=404345
After I upgraded my radio, everything worked fine less receiving media (picture) messages. This thread at xda was the solution. Currently this only works for Verizon subscribers and I can only speak for it working on the XV6800.
Cheers!