so one shiny nokia e65, and a bit of frustration, later; have found the following recipe for getting the phone to sync correctly with iSync.

Firstly download the plugin from Nokia

Then install and if you get a rather cryptic error like this:

[Nokia E65] Device is not available or synchronization was cancelled.
Close dialogs and applications on the phone and try again.
Device “Nokia E65″ synchronization failed

Looks like the Nokia installer drops the plugin into a strange location (originally it allowed isync to work once and then I got the error message

$ cd /Applications/iSync.app/Contents/PlugIns/
$ mv Nokia-E65.phoneplugin/ ApplePhoneConduit.syncdevice/Contents/PlugIns/

Once this is done, restart isync and all should work!