I don't use any Bluetooth items currently, BUT... I do have an iPAQ 1945 that I 'retired' a few years ago, but still keep around for some of the applications (ok, games). It has built-in Bluetooth support, so I dug out the manual and was reading through it. I have to say, this is going to be fun! I'm sure there will be some 'remote control' apps written for the Pocket PC OS and NXT - but just the ability to send basic controls from this little hand-held device is going to be great. There is a LOT to know about BT - my manual has about 15-20 pages dedicated to setting it up, configuring, and using it.
On another subject - I haven't heard anything yet about the MUP. It's driving me crazy waiting.