I enjoyed the first two series of "Mad Men", which I found moving and extremely well-acted. If anything let them down, it was the lack of subtlety in some of the writing: themes were hammered home, and references to contemporary events were crowbarred in rather than allowed to arise of their own accord. On balance, though, I felt the quality of the acting, and the visual stylishness, carried it.
My qualified enthusiasm for the show has been seriously dampened by Series 3. The narrative is running out of steam, and the writing, always overrated, is becoming a real weak link. There's nothing more for us to find out about Don Draper; the younger characters' emotional and relationship problems from the first two series have vanished without obvious resolution, to be superseded by new but unrelated ones; and the show is struggling to find new things to say about either advertising or life in the 1960s.
For the most part, it remains watchable, and three or four episodes from Series 3 are very good indeed. But in the rest, the writing merely treads water: competent but superficial, it's the sort of thing churned out by bored, practised Hollywood hacks. There's no craftsmanship or subtlety; the concern is too much for "stories" rather than themes or psychological consistency. If that makes it sound like a soap opera, well, to be quite honest, that's what it has become. (Incidentally, I reached this conclusion independently of Ms. Williams below!)
"Does it matter?" you might ask. No, of course not - if you want a soap opera. But "Mad Men" makes no secret of its pretensions to sophistication and universality, pretensions that it manifestly fails to live up to in this series. It flatters the viewer's taste and intelligence, without actually engaging them.
Worst by far is the final episode, which is boring beyond description, and whose shouty, predictable dialogue would be an embarrassment in a "Dallas" script.
"Mad Men 3" is still better than most dramas, but I'd hoped to be able to voice stronger praise for it.