[tommi]

Too bad they didn't make the plug really usable: connect it anyway you want to.

There are probably many ways to implement that. An USB concept for it: http://www.wired.com/gadgetlab/2011/01/double-usb-plug-conce...

[gnaffle]

One obvious way to implement that would be the MagSafe connector. Indeed, Apple has some patents relating to data-enabled MagSafe connectors.