Corus announced that Teletoon will be rebranded as Cartoon Network on March 27. The existing Cartoon Network channel will become a Canadian version of its sister brand Boomerang the same day. (Source)
Teletoon's brand had actual value back then. In the late '00s and early '10s, shows produced for the channel were sold internationally to great success. Cartoon Network in the U.S. made plenty off of Bakugan, Johnny Test, Totally Spies, and Total Drama. It would've been silly to kill off a name that was launching hits just to fuel an American brand. Kids here would've been far more familiar with Teletoon's name than CN's at the time.I feel like this should have occurred when they launched Cartoon Network/Adult Swim back in 2012. It never really made sense to me to have both these channels airing program from the same or similar library of shows. They should have either relaunched Teletoon into Cartoon Network in 2012 and rebrand the Teletoon Retro channel into Boomerang back then.