I ate there in mid-March and it was okay. The service was acceptable (so not outstanding, but not awful either). The food was okay, but it really depended on what your ordered. The scallop appetizer (tiny scallops) was okay, but was over-priced. The crab cakes were okay, but others on property were better. The braised beef dish (not on the menu anymore it appears) was good.
We were seated in an alcove area, straight down from the entrance, so the sound really echoed. It made the area pretty loud and it was right on the main walkway path so I got bumped several times.
Overall, the experience at Captain's Grille was okay, but not enough to warrant a return trip when there are so many others places to try at WDW.