Aside from all of the minute details, the two major features are the 8 audio tracks of recording along side the MIDI tracks, and the ability to use an LCD monitor and mouse/keyboard (available as a "future" update).
My only concern is the feature the MPC's have to kick in and out of overdub record and erase record. That is a real creativity enhancer. Sometimes you want to try an extra line on top of what you've just done, and other times you want to go with a completely new track. If the MV doesn't have overdub record, then that's a major sticking point for me.