Whilst Bluetooth is great, would WiFi not be better?
Such a tiny box tucked away and silent, a video feed through a TV (with Risc OSs special abilities here), wireless streaming, wireless internet, wirless USB keyboard and mouse.
All you need is hardware capable of handling TV input & MPeg Codec_ing. Throw in some DVix, PVR software and a pretty OLED display and that's pretty close to the current PC holy grail.
A silent fanless media centre. Although you could add a blue LED fan I suppose :cool
I've no idea what the technical and legal barriers are though.