a AAA game it may be $10 or $15M. That only covers development cost.
No chance, not even close - a studio with 150 people, an average salary of $80k, and a 24 month development turnaround costs $24 million in salaries alone. A studio like 343 had around 350 developers at peak on their payroll during the development of Halo 4 and a development time of three years. With the studio based in Seattle and hiring top-tier staff, the average salary probably met $120k - salaries in that peak period would have cost a cool $3.5 million for just one month. If you're averaging just half that number across the entire project, you've spent over $60 million in salaries alone.
Do a little research and just think about what was involved, then crunch some numbers. It's pretty mind blowing. I'd say the real world development cost of a game like that could very easily be in the region of $300 million.
Having been a professional developer for about two decades, I've crunched the numbers quite a few times, thank you.
While AAA games do include radically new designs, new engines, targeting new hardware, and sometimes taking three years and many hundred people, that situation is the exception. And it certainly does not reach the $300M range.
Most AAA games are incremental releases. They rely heavily on existing technology and can have development teams in the 20 person range with just a few months of development time. They can also have larger teams of 50, 100, or more people, and can last a year, two years, or rarely three years. For AAA game a development budget of $10 to $15 million is fairly common.
Your estimate of $60M is interesting. That was approximately the cost to develop World of Warcraft. (Various official sources have stated different numbers, most between $40M and $60M) WoW was one of the largest video game budgets at the time. A few of the more recent MMOs have begun to reach the $100M mark, but these are the largest and riskiest creations in the industry.