Although many were surprised by yesterday's announcement that Viacom had purchased Teenage Mutant Ninja Turtles for $60 million, co-creator Peter Laird makes it clear the sale of the '80s indie-comics hit turned multimedia franchise was a long time coming.

"Why did I sell the TMNT?" Laird wrote yesterday afternoon on his blog. "There are a number of reasons, but first and foremost is that I have been doing this TMNT thing for twenty-five years, sixteen of them in partnership with TMNT co-creator Kevin Eastman and the last nine as sole owner of the property. That is a long time. It is almost half my life (I'm 55). I never expected to be working on the same thing for this long. And it has worn me down. I am no longer that guy who carries his sketchbook around with him and draws in it every chance he gets. ... I miss -- I really, really miss -- being that guy."

Laird, who in March 2008 completed a buyout of Eastman's interests in TMNT and Mirage Studios that had begun in 2000, noted that his interest in the property had faded in recent years: "As one result, the production of TMNT Volume 4 comics has slowed to a crawl. That's not good. I have a conclusion planned out for that series, and at some point I want to get to it. Maybe this sale will help me get to that point. We'll see."

He also stressed that he still owns Mirage, the company he founded with Eastman in 1983.

Debuting in 1984 as a black-and-white self-published comic, Teenage Mutant Ninja Turtles began as a parody of Cerebus, Daredevil, New Mutants and Ronin. However, thanks largely to the efforts of licensing agent Mark Freedman, the property soon spawned animated TV series, movies, video games and endless merchandise.

Under Viacom's ownership, TMNT is destined for a new feature film from Paramount and a CG-animated TV series from Nickelodeon, both in 2012.