Hopefully a long while yet, i'm still very pleased with my consoles in every way, good games are still being produced, the graphics aren't too far behind PCs yet and the online is still very populated on both. I remember when the PS3 came out, the PS2 looked shocking in comparison to PC games and the complete lack of online really made it only viable for exclusive games, multi platforms were a no brainer for the PC back then, but the differences are still too small for me to warrant an upgrade this time around.
Hell, i've only had my 360 for less than a month.