I'm getting a lot of ICQ's about the one click url that serves as login and confirm so let me go into more detail.
If I have a join page when the surfer clicks join I api that member at that moment to the target dating site. If that target dating site responds with a one click login/confirm url I can simply redirect the surfer to that url and log him directly into that target dating site.
The best format for this url is simply like http://datingsite.com/username=joebl...sword=whatever
And make that url bookmarkable, don't redirect it to home or whatever, make that the home page. Surfers are getting lazier by the day, the less hassle we make it for them to login the better off we are.