Update: Incoming call notifications now work perfectly with the T608. Unfortunately, the options presented on the new dialog (Answer, Log Call, Voice Mail, SMS Reply) do not work. If you have developer clearance with Apple, please file a bug report.
Apple has released version 10.3.4 of the Macintosh Operating System. Joy.
Of relevant importance, improvements to syncronization, and incoming call notifications when paired to Bluetooth devices.