from what I hear you can tag your way up
if you have friends or a guild to help you, you run through a zone taging everything and letting your guild kill it.
for an mboxer it would be like having your main run around solo and 4 alts following him, let your main tag the item and your 4 alts kill it.
this is supposed to give your main full credit for the kill, and your alts get nothing.
it doesn't work well if your alts do some type of AoE.
I'm personally not really interested in do this, I would rather just quest my way up which is going to take a lot of time.
I can see this as a plus if I wanted to push an alt through like getting a druid caught up with my pally/shammy team.