According to the article the company claims they are going to lose millions in sales.
Yeah - I'm sure they are just crushed about all this free publicity. And any recalls or modifications they do will simply be written off.
Anyone - of any age - who wants a copy of the game will be able to get a copy, no matter what rating is on it.
Temporarily they will. It's in the second month of PC availability, this will seriously impede on their gravy time, but over the long haul it'll have little effect, it's not like GTA3 or Vice City dropped in price very quickly. Might hurt them with some places like WalMart, but they've always treated GTA like an adult only game (card you and everything) so maybe not.