For those of us who follow local media commentary, today’s a big day — Erik Wemple, formerly of Washington City Paper and TBD (both outlets where he was not shy about criticizing his current employer), launched his Washington Post blog last night.

So what’s Wemple’s mission statement?

So we’re going to go with a media blog that’s for and about Washington. That’s a catchphrase that’s approaching its third birthday here at The Washington Post. When it first emerged from an internal strategic review in late 2008, I was working for the Washington City Paper. In a blog post on “for and about Washington,” I blasted the phrase for lacking specifics. Time for a retraction: I think it provides a good jumping-off point to describe what we’re doing with this blog, which is to cover media organizations that matter to Washingtonians with a focus on a key local industry: politics, that is.

It appears as if Wemple will be keeping his observations focused mostly on national media — his first two posts, for example, are about the state of newspapers and the New York Times. (“I’ve spent years on the local news front at Washington City Paper and then at TBD, which means that embracing a more national beat will require some orientation,” Wemple asks, in a preemptive plea for Post readers’ mercilessness.) We expected this, but still, here’s hoping that Wemple will carve out some time for local media commentary — after all, he’s got plenty of personal expertise in that field.

One thing we can’t complain about: Wemple’s WaPo caricature, which is pretty fantastic.