I'm seeing current posts, as well as this one, in the Atom feed. You may want to check the Atom feed itself to see if different content shows up (e.g. it may be Reader not loading the subscription quickly enough) or you may want to resubscribe in Reader.

Keep me posted if this continues.

Google Reader seemed to kick back to life later in the day after I wrote this post. No idea what the hangup was, but all of the backlog seems to have arrived. I suspect it was on their end. I'd demand a refund, but since it's free, I guess I'll keep my mouth shut.