Nothing is announced yet, but considering that this franchise is
outselling the once-invincible Haruhi the only thing that would be stopping JC Staff from chronicling further delightful adventures in Academy City is the financial disaster caused by the end of the Earthquake...
...not to mention having to literally rebuild
their own studio virtually from scratch afterwards.
But they DID leave us on the cliffhanger for the "World War 3" Story Arc, so let's not count them out just yet.