100,001-499,999
However there's a HUGE difference between 100,001 and 499,999. The later is a huge success for an MMO (not WoW huge but huge enough). Most MMOs don't get past 100,000 and stay there.
The hurdle STO will experience is the fact that it's a Star Trek game. I'm not sure if ANY Star Trek game has even sold 1,000,000 copies. Maybe that 25th Anniversary thing but I'm not sure. Most don't even sell 100,000 even at Star Trek's peak. Star Trek doesn't sell like Star Wars (as evident by t TOR's sudden huge forum population growth, it's already up to 150,000 people).