The season premiere's been available On Demand for days, but I waited to watch it at its actual airtime so that I could gather my crew and also see the episode in its high definition form (why doesn't Comcast make HBO shows available on HD On Demand?) and I . . . don't have that much to say about it. I will say that I was concerned the show might head downhill and, so far, there's no particular evidence of that. Instead, a comment about the earlier seasons.
One complaint (or perhaps just observation) I've heard from several quarters about the show is that the characters of Omar and (especially) Brother Mouzone break with the show's realism. I've been trying to think of the right thing to say about that, and what I've come up with is that it's a bit akin to complaining that Dr. Manhattan impugns the realism of Watchmen. It's true, of course, that he isn't a very realistic character. What that goes to show, however, is that one's initial impulse to call Watchmen "realistic" is simply a mistake.
The Wire is, in some ways, a very similar enterprise. It's a complicated, very layered, story with lots of internal resonances. It's also very invested in deploying a subversive take on some American cultural archetypes -- cops and police procedurals on the one hand, superheros and comic books in the other. A certain style that one might term "realismesque" (for want of a better term), but realism, as such, isn't really what's on offer. For that, you need to go watch The Corner (legitimately recommended, though it's hellishly depressing).
Once you think of Omar and Mouzone in this context, you see that bits of irrealism are popping up everyone. The show is really very highly allegorical and filled with symbolism of a sort as seen in Season Two's parable of deindustrialization or the small thing of the names the dealers give to their product.
That said, I had lunch with Mark Kleiman last week and asked if he watched the show. He said that no, he doesn't watch any television at all. Then we talked a bit about crime control and drug policy, in the course of which he mentioned -- unprompted and without any description of the Omar character -- that stickup crews are both a real phenomenon of the Baltimore street and actually a somewhat eccentric one not seen in most American urban areas.