The BBC is using open formats, protocols and systems to provide this service.
This is a source plugin for content made available by the BBC, kindly sponsored
by the BBC and Canonical. It's still quite basic, but functional.
(Note: this has nothing to do with the iPlayer, it mostly just makes content
available in totem which is already available in some form or other on the BBC
website now, at least for the time being; server-side things are also still
work-in-progress, so expect the occasional hiccups and problems with the
content in the feed.)
The totem plugin's implemented in open-source python. Go play!