According to the "crunching the numbers" segment on MMA Live this week, UFC 87 did 625,000 buys. They do not cite a source for any of their numbers, which makes me skeptical, but if the number is correct, it is an incredible showing of selling power for Brock Lesnar.
In almost every U.S. market for UFC 87, interest was higher for Brock Lesnar than Georges St. Pierre. It appears he was the primary mover for the buyrate for this show in the states, while GSP brought in a good number in Canada. If this number is correct, Dana's prediction that Brock vs. Randy will do a million buys looks a little more realistic.