There is an updated video meanwhile.
Here is a short video showing the interacting devices (Apple wireless keyboard, iPhone, communicating over Bluetooth) in operation.
Feels like getting closer to the “mainstreaming” goal - it uses hardware that comes of the shelf (unfortunately you still need to have access to a jailbroken phone), uses a packaged application, does not expose bits and pieces to the end user, just works with all the applications that use the standard on-screen keyboard - and finally: it may just help you doing something more efficiently or comfortably.
It uses the Bluetooth stack developed by the researchers at ETH Zurich - they deserve all the credit.
They kept and keep continuing with the development of their BTnode software - so for a most recent version you should refer to the BTnode CVS repository. Everybody with a Linux or OSX desktop system can do his own experiments with the BTnode software in a setup like the one described under A Bluetooth stack in user space.