The "launch with 100 free members" strategy worked extremely well to avoid the classic "chicken and egg" problem. It's hard to quantify, but it set the tone for the community with friendly, intelligent, and experienced people.

As a new member, that led to an amazing first-time user experience where I got high-quality answers to every question I posted.

And now I'm motivated to help out other members just as the first members helped me.

Launch revenue is great, but it won't survive unless it gets this right ^^