You're right of course - we'd need a pretty good setup to be able to cope with that much data! I think that the RED Epic cameras are a sign of what's to come for everyone else within the next 5 years or so. RED are an interesting company, in that they have taken on the existing players in the movie camera business, and put out a better camera for far less money; their original camera (the RED One: www.red.com/products/red-one
) gave film-makers the equivalent of a $250,000 camera for $25,000 - and by doing so, revolutionized the industry. The RED Epic and Scarlet look likely to put similar pressure on Canon and Nikon. Sure, Canon and Nikon will likely be able to beat RED on price - but at the higher end of the market I doubt that they will beat them by very much. One of the exciting aspects of the RED designs is that they are modular, so photographers will be able to upgrade there sensor without buying a whole new camera body; it will be interesting to see how disruptive this is to Phase One and Leaf...
Certainly, at the moment - for resolution - a digital image is not going to beat a large sheet of film, but that state of affairs is not going to last indefinitely - and the trade off with film is dynamic range, processing speed, and mobility (an 8x10 view camera demands a certain approach to image making). We are not yet at a point where film has been consigned to history, but from my point-of-view we are getting a little closer every year. The Canon Wonder Camera (concept) shows where things might be going (www.gizmag.com/canon-wonder-camera-concept/15591
); it allows post-capture focus, among other things...
Also, for those who don't need the resolution of film - but like the aesthetic character of film stock - DxO FilmPack (http://www.dxo.com/us/photo/filmpack/what_is_dxo_filmpack
) is another reason to put your SLR on eBay ;)
It's exciting stuff - and a good time to be alive!