Much of the Blunt code can be now reused, but there are some bigger parts which need to be redesigned completely, e.g. to support multiple active RFCOMM or L2CAP connections. In the end, it should pay off though, having an always-on Bluetooth stack is very handy, especially in the way I use my Newton: during the day it’s always on and running off the AC adaptor, otherwise I’m using rechargeable batteries.
Under the hood, things are looking quite interesting. Working with tasks, ports and messages seems easier than I thought, and the only thing which is a bit open at the moment is memory management. It’s possible to access data across task boundaries, but maybe shared memory would be the cleaner way to do things.