Nickelodeon has renewed the Teenage Mutant Ninja Turtles animated series for a fourth 20-episode season even before the third season debuts.  The fourth season of the TMNT will air in 2015 and will feature Seth Green voicing the role of Leonardo.  Green, who actually took over for Biggs (who is leaving because of the demands of his work on Orange Is the New Black) in Season 3, will continue to voice Leonardo in Season 4.
 
According to The Hollywood Reporter, Nickelodeon reports that the TMNT animated series has been "maintaining impressive ratings across the networks cable and digital platforms."  The series bowed in 2012 and managed to snag over 12 million viewers during its debut week. 

The oft-delayed live-action hybrid TMNT movie is set to debut on August 8th (see "First 'TMNT' Trailer").