How well is the title doing, really? Feels like it's just us 50 people here on the forum that reads it...
I've seen a couple of people on /a/ talk about it before (usually in threads I start, though...), and after four years of hype, I finally got one of my friends to read it (he doesn't have an account here). But yeah, the international reader-base can't be larger than 150 people. I suppose that's enough for Viz to make a profit, since it's been going not-quite-strong since 2003.
So strange that they'd cancel something popular like Gintama but keep Excel Saga going. Not that I'm complaining, I just think it's weird. Though I have a feeling the fact that no scanlations exist for ES might have something to do with bringing them sales they wouldn't normally get...
A lot of people have seen the anime, but no one knows there is a comic at all.
Neither does Viz, apparently; 22 doesn't even appear on their website! The newest one on their official series list and store is 21.