On IHE's around the web feature, entries are tagged with more than a link: they are offered with the preposition "in"--as in, "in blogos..."
I tend to use "at" or even "over at" to refer people to other sites, and the difference is a metaphorical/conceptual one: how we conceive of blogs. IHE, for example, seems to be invoking the usual language of referring to journals and books. One wouldn't say "I loved your article at QJS!" Rather, one would say "in." This prepositional choice seems to be a deliberate one perhaps having to do with blogging integrity, I dunno.
So why do I and others use "at"? Seems to me a more place-based metaphor, and the occasional "over" somehow acknowledges multiple activities going on simultaneously in different places--at stake here is a scenic/dramatic emphasis. ("meanwhile, over at MichaelBerube.com, yesterday's discussion continues.") You get the picture. Speaking of pictures, I'm wondering too if we wouldn't be better served by the language of the more kinetic, surface medium of television channels: "This week on Working Blue, Jenny goes to audiocamp."
