If we assume they've made an average of $15 for each copy sold, they've made $74.25M already. The game sure has been very expensive but so is $74M a huge sum of money, much more than most games cost. I wouldn't be surprised if the budget was like $100M or even more but they're definitely going to make money in the end if they haven't already. They've probably made more money than just $15 per copy. $20 would put the profits at around $100M already.
Also, Prologue I believe, was mostly developed using assets they were going to use in the full game anyway so that one can't have cost them a lot. And if it did, we can probably deduct that amount from GT5's budget.
And before you come screaming how many of those copies were sold at discount, I doubt it was Sony that discounted them (mostly at least). It must have been retailers, no?
