Finished the second series the other day and seriously pondering buying the next. It's just so, so good, although there are some minor niggles with the way it's plotted, as others have pointed out.
One thing that strikes me is that, with the possible exception of the lack of sympathetic female characters, it's generally a very progressive piece of TV. Its two basic premises are the utter inhumanity of a privatized, profit-making healthcare industry and the huge amounts of money and power placed in the hands of extremely unpleasant people as a direct result of the War On Drugs (both those characters that are introduced as ruthless thugs, and what it eventually turns Walt and Jesse into). It does not paint a sympathetic picture of an America which is neoliberal about what people need but paternalistic about what they like.
Further, isn't Walt pretty much the living embodiment of the American Dream? A can-do kinda guy, an endlessly resourceful entrepreneur who spurns charity while taking risks and working hard to provide for his family.
Very powerful and difficult-to-watch, that scene towards the end of the second series where [SPOILER for the benefit of Rich] Walt just lets Jane die and doesn't lift a finger to help to her. That's the precise point where you know he's really turned to the dark side. Once he'd handed the money over there was clearly no risk of Jane going to the police as that would have endangered Jesse, but he feels she's had it coming because she dissed him, she threatened him and forced his hand. Without even realizing it, he's already thinking like a gangster.
[I agree with the points about the plotting, as I said - I almost have to wonder if the writers have watched Peep Show, there's such a highly developed sense of edge-of-the-seat awkwardness. And things go wrong in synchronicity with each other just a bit too perfectly. But I don't think this detracts too much.]
