Well since we know the teams, maybe we should try finding differences between the people in the race... So we don't get confused between people like Shola/Doyin and Kim/Leslie...

So here's what I can find...

Ian/Teri - Male/Female
Jack/Jill - Male/Female
Zack/Flo - Male/Female
Tramel/Talicia - I wonder what.
Michael/Kathy - This is getting obvious!
Aaron/Arianne - No prizes for guessing!
Andre/Damon - Damon (Fireman) looks darker. Same height though.
Dennis/Andrew - I think the moustache is enough.
Gina/Sylvia - AH! SAME CLOTHES! Sylvia has straighter hair.
Heave - Heather's taller, Eve's hair looks straighter.
Ken/Gerald - Ken's a moustache.
Derek/Drew - OK. This one is hard. But Derek seems to have more moustache...

Anyone with anything else?