[pmtarantino]

I think the hardest is the first impulse. To convert from user 0 to user 10 is not so hard (you can invite friends, etc.), but when all your friends are registered, what? How to reach unknown people out there, I think that's the hardest part. People interested, not so publish on Hacker News or something like that where a lot of people see, but there are not a lot of conversions.

[Robby2012]

I agree totally with you, finding the first users is the critical point on every startup when you finally find out if your idea is worthwhile or not