Sprint has approved, and will release on their web site next week the first firmware update to the PPC-6700. This update makes several device-specific improvements, and also deploys AKU 2 for the PPC-6700. It does not deploy AKU 2.2 and thus does not have A2DP support.
The update is currently available on-demand to Sprint Stores, and we are also hosting the final updater at the link below. As with any Windows Mobile firmware update, this will erase all data on the device.