This is a fascinating question, Josh. I agree that we could expand the categories for posts on the site, although I don't know that it's feasible to go back through and re-tag a large quantity of posts that have already happened on the site. DH loves crowd-sourcing, but that seems a bit unwieldy.
I'll agree with Bethany, however, on my belief that the site should remain steered by questions and the community's attempts to answer those questions. In this way, it seems a fitting service of the ACH for fostering and growing the community of people who work on the humanities using / with computers somehow. But there's no reason why an Alan Liu can't come along and ask a question to the effect of "whither cultural studies and digital humanities?" Or someone who has just read one of Steve Ramsay's pieces could ask, "Do I need to learn to code to be a digital humanist." What wouldn't seem appropriate—to me—would be for Alan or Steve to ask that question in a rhetorical way and then to proceed to answer it. A blog or a journal, in other words, this ain't.
