YouTube cofounder Steve Chen (pictured) is leaving the video service, three years after being bought by Google (NSDQ: GOOG), but is staying with the search giant, Peter Kafka confirms. Chen left his CTO position at YouTube last year, and not involved with day-to-day ops anymore. Google says he has moved on to other engineering projects at the search giant. Chen is also reportedly involved with a new incubator-like venture founded by former BitTorrent exec Ashwin Navin, though we haven’t heard much since.

YouTube hasn’t named a replacement for the CTO position, and likely won’t replace him now that the ops are integrated with the larger Google infrastructure. Chad Hurley, the other co-founder, is still YouTube’s CEO, but don’t be surprised if he moves on sometime this year. YouTube has also been under pressure to generate more ad revenues, and guessing game from analysts on its numbers has picked up in the last few months.