Gionta has an NMC this year, but only a limited NTC next year. So after this season, he could be moved or even sent to Rochester.
But let's remember the number one biggest reason he was brought in wasn't for any on-ice contributions. It was for leadership within the room. If he is a positive influence on the kids inside the room, and he's not causing us cap trouble (which he isn't, since we still have plenty of room), then he could still be an asset, even if his play isn't helping win games on the ice.
Unfortunately there's no way for the fanbase to judge that without being in the locker room ourselves (unless anonymous quotes start surfacing). It would be pure conjecture, likely defined by what your opinion of Gionta already was.