Try this: Have your user select some 5 people they would like to date. Once selected shoot an email off to 5 of the user's friends asking them to have a look at the prospective date's profiles and tell which would be most appropriate for the user. Then confirm with the user and setup a date.
DISCLOSURE: This idea is not my own. I read about it somewhere, most probably a previous HN thread.
DISCLOSURE: This idea is not my own. I read about it somewhere, most probably a previous HN thread.