The video in the last post revealed the launch date as being 2012, now here's a little more info also found by tone-master21.
From CableTalkTV.com (my bold):
... And in fourth quarter 2012, Nickelodeon will premiere a new CG-animated version of the wildly popular franchise, Teenage Mutant Ninja Turtles .
...
Based on the iconic hit franchise, Teenage Mutant Ninja Turtles has been greenlit for 26 episodes and will be executive produced by Ciro Nieli, Joshua Sternin and Jeffrey Ventimilia. This half-hour CG-animated action-comedy series breathes new life into the wildly popular band of reptile brothers. The new series begins as the turtles emerge from their hidden lair in the sewers for the very first time, ready to confront the wondrous and hostile world of New York City and face enemies more dangerous and pizza more delicious than anything they could have imagined. Funnier and ninja-ier than ever before, the show will explore the camaraderie of four teenage brothers learning to rely on themselves and one another as they unravel the mystery of their existence and grow to become the heroes they are destined to be.
As this entire press release is about Saturday morning cartoons, it seems safe to assume that's when we can expect it to be scheduled. And there's one more detail taken from Yahoo.com (again, my bold):
The presentation also featured the first-ever sneak peek of footage from the brand-new, CG-animated Teenage Mutant Ninja Turtles, revealed by actor Jason Biggs, who will portray the voice of Leonardo in the series.
It's been previously revealed that Rob Paulsen, the original cartoon voice of Raphael, will be playing Donatello in this series (woohoo!), so that's two out of four Turtle voices revealed. At the rate Nickelodeon is suddenly dropping TMNT info, surely it can't be too long until we find out the others.