I took 2 million as the other 400k probably wasn't at full price hence made it to complex, I think 2 million was around launch though.
---------- Post added 2012-09-29 at 01:00 AM ----------
The cost of day to day operation is hardly worth a footnote in their quarterly, month to month development with 500 developers at $50k a year is $2.08m which translates to 173334 subscribers (@ $12 each ). It's far from expensive to maintain a MMO, something that few gamers seem to understand, sadly as it gives the developers the opportunity to under deliver while over charging.
Only thing expensive about an MMO is to make the original product.