I'm pretty sure I was not hallucinating... Earlier, when I was reading the Developing with Google App Engine, Part I in my RSS reader, I noticed some spammy links at the end of the article (the kind offering
free stuff). I visited the original page, and surely, there it was.
It all seems to be cleared up now (they also reissued the feed). This one again shows that these days there is no such thing as
sites safe to visit. I'm also awaiting the result of their investigation (hopefully the publish something so that attention can be raised about these kinds of attacks). I suspect that it was an SQL injection, but I have no way of knowing.
Update: they didn't publish a statement yet. I've sent an inquiry to them about the matter, but have yet to receive any reply.