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.
It's a little different but it feels amazing. A new chapter in my life and I'm excited. It's been amazing. Better than I expected. The weather is great, the place is just amazing. I can't say enough good things about it. I'm glad to get the season going.
— Ryan Kesler on his transition to the Anaheim Ducks