Thanks for posting this. We set it up the other night and have already had a stack of people join.
The Nissan Z / Infinity G group we set up last year is crazy active and has over 175 local guys in it. We wont get those numbers for M cars but at least there will be a more convenient web-locale to congregate.
Its critical for supporting meets and quick & dirty for sale ads.
The forums are always better for more detailed discussions though.