All this talk about cabling leaves me to ask the question (especially as someone waiting for his new bike that will need cabling) : Is there any real difference in the quality of brake or shift cables and housing?

I ask this because I see generic cabling that might run for $5 a set, all the way to premier cabling that might be $80 bucks, and of course everything in between. Is the difference of quality so much between them and in between that you should not consider anything but mid and upper tiers of the cable and housing? Or is it just another way to pry dollars from our wallets and the quality isn't that much of a difference to matter?