Well, I think its a interesting change from the 'find this guy kill him and take his car'.
For anybody that doesn't know. This mission involves you going to the beach, and talking up this girl that has a 'kickin van with huge speakers in it. Your job is to steal the van for OG Loc, so he can throw a good party. You have to talk up the girl that owns the van, then dance with her until she says something about going inside the van and getting a little closer.
The dancing works alot like DDR or any of those games, you basically have to hit whatever buttons it asks for, but it only asks for the T,S,X,O buttons which makes it a little easier. Its somewhat tricky and frustrating though as you'll hit the right button when its in the square but it wont say perfect because it wasnt exactly in the middle even though its only in that spot for tenths of a second. =)
The LowRider challenges work the same way, except rather than seeing CJ shake his booty, your car bounces, its cool to watch, but when you're playing you're concentrating on the button mashing so much you don't get to see it :/