Then why bother releasing it in the first place? If the game garners 7/10 or 6/10 reviews, they'll have lost money on the port anyway.
Atleast if they had worked on getting Source running properly on PS3 they could make a profit when they release Episode 3.
I don't think that the reviews are going to have much effect on sells, because the PC and 360 version has been getting so much praise any one that is waiting on it will probably just pick it up thinking they took the extra time to do every thing right
I willing to bet Valve made most of there money off the PC version and the only reason they probably did the ports in the first place is part of the distribution deal with EA because it would suck for EA only making money off retail boxes for the PC