Gin Tama is hard to describe without sounding like you're mashing together half-remembered pieces of several, very different manga. It's set in the Edo period, that's been taken over by aliens. The technology and culture is mostly modern (at one point, the main character cuts out of the storyline to buy the new Shonen Jump) but with a few SF-ish touches here and there for the sake of the storyline. And it's the sort of comedy series that will throw everything at you in the hopes that something will stick. And the art? Quite good, detailed, with some imaginative twists. All that said, I'm still not sure what I think of it. I'm pretty sure Sorachi has done exactly what he set out to do here, and it's certainly unique. I think I'll stick with it, at least for a few more volumes.