Oh how I long for the good ole days .. when all we had to worry about was writing for 15" monitors ..
Really tho' .. Responsive Web Design could have come along a lot sooner than it did .. even so, I'm glad it's here and gaining ground.
As an added note: The PC and the Mac will never go away as long as there are guys like me around. Sure I have a mobile device or two .. but I can't use them in my business to actually build anything.