Oddly enough, the NY Times liked it the most.

Grand Master Pudge: Jack Black's Doughy Dreamer Turns Jedi Knight in 'Kung Fu Panda'
By John Anderson
Special to The Washington Post
Friday, June 6, 2008; Page C01

'Panda' not a knockout: Jack Black's kick outshines the film's creativity
Jenny Mayo
Washington Times Friday, June 6, 2008

This movie has been designated a Critic's Pick by the film reviewers of The Times.
Fuzzy Outsider, Kicking His Way Toward His Dream
By MANOHLA DARGIS
New York Times June 6, 2008

Scott Moore interviewed Jack Black of the new animated movie "Kung Fu Panda" for "Dude, That's So Skidoosh: Behind the Microphone, an Inner Voice -- and Barrel Kicks," Washington Post Sunday, June 1, 2008; M14 and "Getting to Know Jack Black."

And here's an article on the movie's background - "Call them martial artists: The directors of the ambitious "Kung Fu Panda" break animation boundaries," by COLIN COVERT, Minneapolis Star Tribune May 31, 2008.