Insomniac will make a game every year...
In many cases it is because the development tools are quite tricky because of the large jump in hardware (weren't the PS2 ones quite hard to use at first as well?)
Anyway, next time I am sure that they will make it slightly less hard for developers after all the criticism that Sony have got over the issue, and the inferior ports that we used to see.
For Final Fantasy XIII, it is their first game on the system, and it will have only been 3 years for those of us in Europe!
GT 5, well they are making the most detailed cars ever, it is just ridiculous
Team Ico release a game every 4 years
Guerilla are making sure that KZ2 is a hit, and given they are a developer with very little experience, their first games are going to take a long time before they become more experienced and efficient







