The thing that worried me is that the founder said they didn't launch at SXSW because he wasn't a fan of conferences. It was on within a few days of launch and seems like the perfect proof of concept for it. When you have just been funded for so much who cares about your personal preference.

Either that or you need some kind of exclusivity in niches to build a critical mass of users like Facebook with colleges. Google Wave was a great case for the path color has gone down not working, people getting into the app, not seeing anyone else to interact with and forgetting about.

Even having a fake persona in it that you can delete, just to give people a feel for how the app works would be better than what they have now.