At London's comic-con this last October, the animator's of Attack on Titan had a panel. It doesn't give confirm-able, new information, but it seems like its leaning much more towards yes than any of the other news I've heard.
"The first audience question, delivered in Japanese, asked when a new season of Titan would be made. Wada drolly responded that the show was really hard to make and the staff needed a rest. However, he knows everyone is looking forward to it and although he can’t make any specific promises they’d like to make it in the not too distant future