Gordon Weakliem thinks that Google was redirecting his subscription to Jon Udell:
I suppose it had to happen - Google Reader seems to have gone insane and replaced my subscription to Jon Udell with an apparently random selection from various Wordpress blogs. It seems like a rule of server based aggregators that they become flaky as they scale up, and there's usually issues with feed identity and redirects right in the mix in every case I've seen.
I don't think this was a Google problem. Why? Well, I saw the same thing yesterday in BottomFeeder - which is a client side aggregator I wrote myself, so I was pretty sure that the problem wasn't on my end. Now that I've seen someone else mention it, I'm thinking that the service being used by Udell (and the random site that kept getting swapped in) had problems.