Okay there will be a poll on the right side of this site vote there. The question is Data, an android, created by Dr. Noonian Soong, who is unable to feel emotions, unable to dream, unable to understand humor, or even use conjunctions. Is considered a sentient being by Next Gen. standards. Now when I'm talking about Data I'm talking pre-movie Data, NOT when he gets the emotion chip.
Now there are two side to the argument I shall do both:
Q did give him the chance to experience laughter. He is aware of all around him and the fact he's not human. He knows and understands this. He is constantly in search of what makes people people. He even became despondent when Lal died. He is therefore sentient.
He is a machine, they do what we tell them to do. He is cold and can barely grasp the use of idioms, sayings, and humor. And while he can grasp that he isn't human that doesn't mean he IS sentient. He's only aware of his surroundings because he's a machine programmed to be like that. He is therefore not sentient.