"A common interaction method for all of my electronic devices"
What he meant was that switching on his telly and selecting a channel, recording a program on his PVR, operating his iPod, starting programs on his laptop, selecting a destination on his sat-nav, looking up a contact in his phone (and so-on) should all share some common usage paradigms.
Apple have got this closer to right than most with iTunes and the iPod: if you can operate one, you can probably operate them both and the idea of the iPod click wheel is (excuse my opinion) one of the best bits of industrial design of the last 20 years. Microsoft have tried to move console and PC gaming closer together (in terms of the user experience) by pushing developers towards a common interface device (the Xbox controller). On a side note, why oh why don't games just take over your PC and start when you put in the DVD?! Yes, I know, security, security... But it' my PC and surely I should be able to make the decisions about what I put in it! (Rant over, back to the main topic).
So what could we do? Well, as individual developers, probably very little other than follow emerging patterns, but this is often contrary to the desire to be innovative. Perhaps only large companies that manufacture a range of devices can foster these visions (Apple, Sony, Microsoft and so on). Despite these potential barriers, I think that good user interaction design will begin to solve this problem. In order to design products such that the user experience is a positive one that engages them with tractable methods, aren't we trying to tap into some "universal interaction ideas" that pre-date software and electronic devices? I stress begin to solve the problem, because this idea of a core vision that underpins all interaction design is a Big Idea and requires coming up with ideas that transfer easily from PCs (that have a keyboard and mouse) to games consoles that have a controller, to phones with a much more limited physical interface and sat-navs with just a button or two.
Who knows, maybe such universal concepts may be over the horizon. I'd hedge my bets and say it's not immediately possible while technology companies are competing to be the one with the next big idea. Maybe the user utopia of common interaction is a commercial dystopia of complete domination by one or two manufacturers. One thing's for sure, we shouldn't stop trying on a product-by-product basis to improve our users' experience of software (and hardware).