[jrnkntl]

This is indeed a namespace thing, every posterous blog uses the same global namespace. They said this will be changed.

See http://news.ycombinator.com/item?id=1443020

[ydant]

There are little quirks in the service that make it seem pretty obvious the (first) custom sub-domains and then (later) custom domains were added on later. The namespace issue seems downright silly until you remember that fact.

Now that every blog is on its own subdomain at the least, I'd imagine this could be cleaned up - hopefully with the ability for custom URLs at the same time...