I am at MFb and it is awesome. I just love it.

6 days - 137,000 Users vs 3000 of FB in the ENTIRE FIRST MONTH
Alexa Ranking 46440th site in terms of traffic out of over 6 BILLION WEBSITES

Checkout this blog by one of the founders for all your answers. Do check his intro to see the credentials: http://www.omerzaheemeer.wordpress.com

It is for all the nice and decent people. So I hope to see you there soon.