Well, I've been looking into the best way of emulating an HID keyboard. If I end up going with an at* microcontroller, V-USB would be the most logical choice. However, it may be best to use the bluetooth chip's SoC to handle the USB if possible. For example, this might be possible with the Texas Instruments chip, however it may not be with the CSR device. Further investigation is most certainly required. 

There's always bitbanging USB 1.1......or not...