This figure makes no sense to me. Even assuming it's targetting a very specific population that I share no connection to, it's still a ridiculous figure. The biggest (in revenue) dating website in France (and apparently, in Europe, too) is Meetic. It had less than a million registered users in december 2010 in total, including other companies in the group.
After a quick search on independent consumer satisfaction services, turns out there are a lot of people whose accounts were created through fishing or the likes, or even without consent. Just by reading the tons of user comments, this really looks like a major scammy, fishy, spammy and illegal service (illegal at least in France, since it refuses to comply to our Privacy & Freedom directives).
There are some satisfied comments, too, so this service probably works well enough in some ways, I just can't take these figures at face value.