Is this the start of the cloud computing dystopia that Stallman warned us about?
Even open source web applications don't have this freedom... If wordpress.org were to do this, those users would be in the same boat.
I've been working on an open source infrastructure project to fix these issue for a while, but it's still pretty nascent. My "manifesto" on that is here: http://bit.ly/forkolator
It's pretty straightforward to self-host your own WordPress blog. Does WordPress not offer data dumps? WordPress users would be in a very different boat, because they have all the tools they need to rehost their blog, without building anything from scratch.