Potentially it removes it altogether because you could do a more traditional "scale up". Picking a few dates a week in a small region initially you only need a few users (sub 100 probably) to fill up the slots.

Then with luck the membership should grow by word of mouth.

Matching people DOES require a huge amount of people to stand the chance of finding a geographical and personality match. This idea of date oriented meeting seems to nail the first problem perfectly.

@OP: I think it's got legs, serious legs. Though I see a problem with no-shows (I guess the 3 or 4 "couples" per date fixes that somewhat). The question is how do you monetize?