Yes, No.4, sooner or later someone will try and release Sim Rapist, or Sim Paedophile, after all with these crime simulators being quite popular eventually they will run out of socially acceptable crimes to simulate.
I think that to believe the "it's only a game" defense of violent games, you really have to think that it's okay to murder in a game because "it's only a game" - in theory you could say the same about a game that would let a gamer play a serial rapist. Both are crimes, and you dont get the death sentence for rape or paedophillia in the real world (afaik).
Honestly though, I did enjoy Vice City for a couple of weeks, but now when I play it I just like to drive around and listen to the radio. It's the only crime simulator I own, and it's probably the last - I don't object to the content myself, but it just doesn't have lasting appeal.
Releasing Manhunt on PC is a dumb idea. That game was banned in New Zealand, so if it's available on PC then kids can download it on Kazaa etc which kind of makes a mockery of the rating it achieves in other countries.
For the record, I think a game that let's you play a convicted murderer, and one that simulates murder, is probably the most irresponsible idea for a game ever. Now a game that let you play the part of Jason Vorhees is a different matter entirely as for one thing he's not really human and he always gets killed in the end.