I think that frequency of brousing Twitter is much higher than that of doing facebook, as far as I watched.
Surely, the result would be true for Twitter users. I often see users who don't(most of them 'can't') date with the opposite sex.
By the way, my senior researcher seems to have tried to use facebook as a online dating website only to result in spam report by a user, Though I don't know whether it is true or not.
