Intertextuality - Webster's New Millennium™ Dictionary of English
the whole network of relations, conventions, and expectations by which the text is defined; the relationship between texts

My wife read me this quote from the book How to Read Literature Like a Professor. I loved it. One reason is that INTERTEXTUALITY is such a cool word. Another is, intertextuality is such a cool concept. I used to just call it innovation, but this word says it with so much more flare. Ok, you got me, it actually only applies to text. But it could convey so much more.

The thing that has always fascinated me with innovation is the pairing of the unlikely (or likely), the application of the obvious, the explosion of the new from that which already was, and in each case, creating a new, richer, more meaningful value. Not that those are the limits of innovation, just that those are the things that I am drawn to.

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Think of intertextuality in terms of movie westerns. You're writing your first western: good for you. What's it about? A big showdown? High Noon. A gunslinger who retires? Shane. A lonely outpost during an uprising? Fort Apache, She wore a Yellow Ribbon -- the woods are full of 'em. Cattle drive? Red River. Does it involve, by any chance, a stagecoach?

No, wait, I wasn't thinking about any of them.

Doesn't matter. Your movie will. Here's the thing: you can't avoid them, since even avoidance is a form of interaction. It's simply impossible to write or direct in a vacuum. The movies you have seen were created by men and women who had seen others, and so on, until every movie connects with every other movie made. If you've seen Indiana Jones being dragged behind a truck by his whip, then you've been touched by The Cisco Kid (1931), even though there's a strong chance you've never seen The Cisco Kid itself. Every western has a little bit of other westerns in it, whether it knows it or not. Let's take the most basic element, the hero. Will your hero talk a lot or not? If not, then he's in the tradition of Gary Cooper and John Wayne and (later) Clint Eastwood. If he does speak, just talks his fool head off, then he's like James Garner and those revisionist films of the sixties and seventies. Or maybe you have two, one talker and on silent type -- Butch Cassidy and the Sundance Kid (1969). Your guy is going to have a certain amount of dialogue, and whatever type you decide on, audiences are going to hear echoes of some prior film, whether you think those echoes are there or not. And that, dear friends, is intertextuality.

How To Read Literature Like A Professor, Thomas C. Foster, HarperCollins, 2003, p. 190
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I generally like remakes, especially when they don't follow the original movie to the letter or when they bring in the modern element. For example, the Island was an awsome remake of Logans Run. Same story, but different. It had a new twist, new value, new context. It took something that was and applied it to something new, and it worked.

That is innovation. Purchase music online, manage files on your computer, play music on an MP3 player. All existed long before Apple sold any of it. Bring them together with an online store, into the music library softare and play it on a sleek and sexy device, and you have the powerhouse innovation of iTunes and the iPod. The echo's of the prior art can be heard loud and clear.