I thought it was alright - it was long, but I blame the constant commercial breaks more than anything else for that. There's really no reason this should run more than three hours, but for a while it was 'award, commercial, award, commercial, award, commercial, etc.'
MacFarlane did OK - he's got a good stage presence, timing, and singing voice. (I did like the focus on musicals/scores). A few of the jokes were groaners, but nothing as bad as what some people feared from him, I think.