Locally, that is. It seems like posts are missing from communities that were made before a day or two ago.
EDIT: To be more precise, I can only see posts in local communities that were made up to 4 days ago. I'm experiencing this behavior both with Jerboa and the web UI.
UPDATE: Sorting by Active or Hot is what breaks things. Once changing to sort by New, all community posts show.
Stupid question: In your settings, do you have "hide read posts" checked?