"Yes it's true, I'm leaving my family at Epic to join my new family at Irrational in Boston starting tomorrow," he said on Twitter.
"And yes I've played Infinite and it's amazing! Can't wait for you guys to get your hands on it."
It was confirmed earlier this week that Irrational's director of product development Tim Gerritsen, who directly managed the content creators for Infinite, and art director Nate Wells, a 13 year veteran of the studio, have both left the company.
Irrational boss Ken Levine said on Twitter that Wells has been quickly replaced: "Scott Sinclair, art director of Bio1, back in the art director's chair for Infinite to bring it home. Can't wait to show you what's cooking."
Back in May publisher Take-Two delayed the BioShock Infinite release date from this October to February 26, 2013, but one analyst remains sceptical it'll ship on time.
"We suspect both GTA V and Bioshock Infinite could realistically slip into a fiscal '14 release period," says Mike Hickey of Janco Partners, meaning they wouldn't launch until after March 31 next year.