[citation][nom]A Bad Day[/nom]I'd give it at least 3-5 years. Many games still don't support more than four cores, which is why the i5 Ks are often considered better value for gaming than the i7 Ks.[/citation]
Sorry, but nitpicking here.
Most desktop i7s are quad core parts just like most desktop i5s. Furthermore, games don't see cores. Games see threads, if even that. It would be accurate to say that most games do not utilize more than four threads very effectively if at all and that wouldn't imply anything wrong either.
EDIT: Also worth mentioning is that the number of gamign situations where higher thread CPUs such as six to eight threads are getting better and better utilized as time goes on, so for the sake of decreasing the chances of an upgrade being important any time soon, higher thread count CPUs can be helpful.