Excellent! Sprint PR has contacted Marc Hedlund who wrote a sharp complaint about Sprint disabling dial-up Bluetooth on the Treo 650 this week. Sprint says:
Due to some development deadlines, the phone has been launched as described, without the DUN [dial-up networking] capability. However, as part of a scheduled maintenance release of software (timing pending some testing), the DUN capabilities will be supported. We also support the functionality in the just released PPC-6601 (Pocket PC device).Very good news indeed. Bring it on!