DVD (Season 4, new to the collection)
"Weeds" was good in its first season, great in its second, and nosedived for the third, to the degree that most of the people who convinced me to watch in the first place gave up on it completely. I hung on, barely, for a fourth season that seemed dissociated on first viewing. Showtime has earned equal if not greater status than HBO in terms of justifying its subscription fee with original programming. What's more, it's embraced HD and On Demand more readily, making stuff like "Dexter" and "Weeds" play in a direct-to-DVD-like format that suits that their fast-paced, novelistic storytelling. So their decision to keep things going, albeit in radically reformatted fashion, seems a good call.
On DVD proper, watching Season Four again makes it seem like more of a full-fledged comeback. The show's writing has found its timing again and there's more funny lines, although the series does miss the characters it lost in the fallout from Season Three. The pretext for keeping Doug (Kevin Nealon) around is flimsy but the show totally needs him; his misadventures with Andy provide some needed B-plot wackiness.
The fourth season benefits from a shorter order of episodes than the last, which spread too few story points across too many episodes. The first season, even as a short order, demonstrated that gradual, sitcom-like pacing didn't really suit the tone of the show. The second season had weddings and pregnancies and murders at every turn, which was thrilling but kind of burned up the show's premise by the really dreadful third year. Creator Jenji Kohan took things to their logical conclusion by burning down the planned community of Agrestic, and by extension her show's original premise, in the final episode. Season four still drags a bit at the end at thirteen (half-hour) episodes, but by introducing an entirely new setting and accompanying characters and themes, Kohan gets a new shot clock. She can take time to set things up before appropriately hitting the gas pedal at season's end. It will be interesting to see in the next season, which begins this month, whether such a drastic overhaul will occur again. It would suit the spirit of the show if it did.