Interestingly I think that while "bladerunner"(1982) the movie seems very much cyberpunk, "when androids dream of electric sheep"(1968) is more of a post-apocalyptic novel. Humans are actually dying out on earth in the wake of a world war. The city of "bladerunner" seems to have a bit of schizophrenia about whether the world is crowded or empty, that of "when androids..." is nearly empty and everyone who can afford it is fleeing earth (most of them already have).
The mcdonaldization of the world seems to me to be what cyberpunk transformed into in books like snow crash. Does that have it's own name nowdays? This is a highly suburban dystopia where government melts away while immortal amoral corporations persue thier own ends independantly of any human wants. Sort of the ultimate tragedy of the commons.
Now what should shadowrun do? I would be inclined to stick to cyberpunk + magic in world setting. The rise of asia, fairly weak government, powerful corporations, massive disparity. It is fertile ground. I don't think it matters that it is 20 years old. I don't think a significant fraction of the youngster market is any more familiar with newer sci-fi than they are with that of the 70's and 80's so I doubt they would really notice the difference. The thing that really prevents shadowrun from feeling more like cyberpunk or more recent sci-fi is the fantasy elements.
Paranoia has staked out the 1984 territory and seems to be doing well enough.
Seems like there is a big gap where a 'fallout'/'mad max' survivalist style rpg should exist. I vaguely remember that it has been attempted several times, but never quite flourished (could be there is one though).