AllanP, thank you for the rendering. Can I ask, which packages are you using to sketch those images?
Also, I love your Avatar, that was my all time favorite set before I discovered the new studless pieces.
The price point I was hoping for would definitely be in the PF accessories range. Around US $15 tops.
Trekman, I completely agree. I love the mechanical solution but it's just not always practical when more functions are needed, or where space is limited.
The turntable is definitely meant to be an accessory and would likely not come with any set. It's for the die-hard fan, someone who has all the power functions components. (which also do not come with sets, such as XL motors, speed controller, etc.)
I do agree the manufacturing costs and reliability of contacts could be prohibiting. But if LEGO is able to use a sealed off the shelf component for the slip ring, it may be extremely reliable and cheap.
Dikkie Klijn, it would be preferable to have the connections fully wired. That way, in the future, new uses of the part are not limited by earlier assumptions about the wiring. It's always preferable to have a "fully wired" cable rather than a partially wired cable. This will ensure that in any extreme uses cases (mismatched power supplies, mad scientist hacking, NXT sensors) all will work with the turntable since no assumptions about the "content" of the wire have been made.
I have submitted another Cuusoo Power Functions component, I'm excited to share it with you all when it's published!