Hi Peter,
Believe me, you are not missing much.
I was given a Serene a couple of years ago for a significant birthday. It was bought from a B&O dealer in London, and there was no software with it. According to the manual I had to go to the Samsung (!) website to download the software to allow it to sync with MS-Outlook on a PC - but for calendar events only. Contacts can only be synchronised with a Beoline directory!
When I visited the website I could not find the software mentioned. As I keep my events on my Palm anyway, the already limited sync software would be of little use to me.
You can't use it as a bluetooth modem for a computer (i.e. can't connect from a PC through the phone to the internet). I used to be able to do this with my Palm and Motorola Razr.
The only thing I have successfully used Bluetooth for is sending/receiving contacts and photos. Even then, the photos have to be less than a certain size for the Serene to display them.
I'm just DYING for the 3G iPhone to come out, and as long as it can edit Office docs, I will happily get rid of my Serene and only reluctantly get rid of my Palm and the Louis Vuitton case for the Serene - now that IS beautifully made.