There was a three year gap between Kung Fu Panda and its sequel. The next movie in the series is coming next year, about five years after the 2nd film. This should tell you that for once, the studio isn't trying to "milk" the franchise but instead trying to come up with a follow up story that's worthy of its predecessors.
So yes, Kung Fu Panda 3 releases in 2016, and here's a hilarious trailer of the film. And yeah, it stars Bryan Cranston too.
Source - DreamWorksTV