Muscle Pharm will be the only supplements sold by the UFC store for 2 years. As long as MP holds up their end of the deal I can't see a contract that would allow the UFC to back out.
You are partly right. No exclusivity meaning that they are not the sole sponsor. There are a couple other companies with sponsorships. MSLP would not be knocked out, they have a multiple year deal. This may turn out to be a great investment. Time will tell.