I quite like Extras, but it can be a bit smug at times. The parallels between Andy and RG's own experiences mean that the second series is often little more than an exercise in navel-gazing.
It has some funny moments (most of them courtesy of Barry and the agent) but the celebrity cameos are starting to grate as are the painful to watch bits (the scenes from series two, episode one featuring Maggie and the actress from hell were not funny, they were just painful to watch and I had to leave the room during the David Bowie scene). I would rather see a greater emphasis on the relationship between Andy and Maggie (IMHO this provided the bulk of the laughs during the first series) and less of the celebs poking fun at themselves.