I think it's a combination of time spent on site/consistent winner + big recent upswing. At least that's the case with me and with another buddy of mine who played here.
I prob grinded about as much as anyone can grind given the volume you can do on this site, which was about 30k/hands month.
I didn't do any abusive chat or other **** beyond the average player, lol. I'm in U.S. and never MA'd.