So, sure gays can sign up, but if I remember the case correctly (I mean it was a number of years ago). The custom software would not "match" males to males (or females to females). Gender preference wasn't one of the items that was selectable it was hard coded into the algorithm. IIRC a gay man or lesbian could sigh up, but they would only be matched with the opposite gender. Now they have "Compatible Partners" which does offer same gender matching, the link is right on their website.