Instead of getting 50,000 users all over the country, get 10,000 users in a city, or 25,000 in a region. It’s much more logical and useful if users can see people and events fairly close to them (a short plane ride for a weekend jaunt). I am assuming their target market is the 20-30 something energetic, good-looking group that probably have decent jobs. They can afford to take off early Friday for a weekend.
That being the case, it’s more valuable to their customer to have a solid group of people and reviews within my geographical area. I’m in San Diego. I don’t care about clubs in Chicago. I want to see hot girls and DJ’s in LA, Phoenix, and Las Vegas. The probability of me actually meeting someone and hanging out is much higher when the geography is closer to me.
Also, as depth and breadth expands, so does the costs associated with properly attracting the market.
Bottom line – focus the site. Geography first.