Blue Jackets general manager Scott Howson announced the deal on Tuesday night.
The 26-year-old Letestu has one assist and two penalty minutes in 11 games with the Penguins this season. He had 14 goals and 13 assists and a plus-4 rating in 64 games with Pittsburgh last season and ranked fourth among NHL rookies in game-winning goals (three), seventh in power-play goals (four) and tied for 11th place in goals.
The Alberta native was signed by Pittsburgh on March 22, 2007, after he spent one season at Western Michigan.
The old saying in hockey is 'weather the storm.' I put the notion in their heads that we don't want to weather the storm, we want to push just as hard and matched their work ethic. I thought our guys exceeded that in the first period.
— Edmonton Oilers coach Dallas Eakins after their loss to the Nashville Predators on Thursday