The piracy issue is a legitimate point that should translate to higher overall sales, but will probably be more than offset by the overall current smaller user base of both the 360 and PS3 combined. I don't think the reduction in piracy will result in millions of extra copies being sold. Still, I expect to see higher sales over time as the 360/PS3 user base continues to expand with a high attach rate and protracted overall sales.
Although the smaller user base is not reason enough to believe GTAIV will sell less than GTA:SA, keeping in mind the attach rate of SA at the time. It was significantly lower than the current attach rate on either console today. Of those 100+ million consoles, how many belonged to consumers not in the GTA demographic? Quite a few.







