ironmanDX on 08 January 2014
Hard to say. Your calculations seem ok though but you forget that not everyone would buy it at launch for the full retail price. Of course, that would also be hard to judge. It's a new IP and really can't be compared to the likes of Killzone, let alone CoD.
It would be at least $100 million though. Perhaps more if MS bought the series and not just the first iteration, hmm... I'll wait till the thread develops a bit more and other theory get discussed before making a full estimate!! 
