The decay of civilization is also a major theme in Foundation. As the Empire goes down, it brings both social order and technology know-how down with it.
This aspect of it might be a tougher fit. While an argument could be made for casting Wintel or Dell or RIM as the decaying Empire, Apple's rise to prominence comes too close on the heels of their decline for there to be a "dark age" corresponding to the one in Foundation.
Another approach might prove more savvy: instead of casting a particular company or set of companies as the Empire, focus instead on the decline of computer literacy itself. I don't know exactly what I mean by that: but I suppose it could be the decline of "hacking"; the decline of the home-grown programmer; the PC market's overall failure to encourage programming-literate creatives; its tendency to incubate monopolies of poor-quality software and hardware.