Are you serious? DVD ROM drives have been pretty much standard in PCs for like three years. I've been waiting the day when I stop getting 4-disc distributions of the games I buy, it's getting absurd. Also, this will help cut down piracy a bit, at least for a small while. The warez people will no doubt find ways to bypass, but it's more trouble.
I myself have a DVD+RW and it's fantastic, but I know I'm not in the general gaming populace. Still, you can get a perfectly capable DVD ROM drive for $50