I myself am a gamer, and a 13 year old one at that. obviously, you'd expect me to be biased towards games but ...
3 year olds do not needs games full stop. maybe a bit of tv, but they do not need it.
get them a ds when their around 5 or 6
I myself have a playstation 3 complete with all mannor of games of which I know you'd love to crow about (hence several 18's, bioshock 2, fallout 3, etc) and at my age, its ok to have these types of amazing games. all you have to do is peel away the mask of innapropriority and controversy to find a truly amazing game.
you may argue that kids become obsessed with games and they inspire kids to do dangerous things.
give you and example. johnny, falls out of a window while trying to secretly buy halo 3 for xbox. the parents, too dumb to see its their son's fault, obliviously think it's the games fault, dont punish him, complain to the games's developors.
the games shouldn't be banned, kids who will are dumb enough to do things like that should be banned from playing them. all it takes is one thicko breaking his leg and ruining a amazing game for thousands of other children.
I have been playing 15's and 18's for years and i'm not dead/murderer/arsonist/rapist etc