Morrison had already done the tag team thing with Joey Mercury when they were in MNM together. Not sure how long Miz was around at that point, all I know was he had a run on ECW with Balls Mahoney and I used to think he sucked. I really wasn't aware of anything he had done until he WAS already teamed up with Morrison.
I seem to recall Miz hosting random diva bikini (or maybe it was dance?) contest before he teamed up with Morrison, so the team definitely helped him.
Although Morrison has lost some steam recently, I'd still say that they're both pretty equal in popularity and card placement at the moment.
EDIT:
I bet half of you at one time used the word "gay" as a replacement word for saying something stupid or dumb.
Every single day...