jefequeso: what exactly are those?
Miaghstir: Fair use: You are allowed to use small portions of copyrighted works, provided you do not sell your compilation (say, Wikipedia displaying the cover art to music albums).
Mashup: Combining multiple pre-existing works (parts of, more likely) or a pre-existing work with something new to create something new (say, much of youtube, for example the already-mentioned Hitler rage videos
like this one about SOPA).
These are currently perfectly legal, but SOPA would undermine this and force Youtube, Facebook and others to either methodically go through each and every newly-uploaded "thing" (video, audio, image, text... depending on the site) to check if they contain anything that
might be part of a copyrighted work (and probably just remove everything uploaded earlier just to make it easier), or simply close down.
SOPA and PIPA does absolutely nothing against the pirates they so like to rage about, instead they and related ideas threaten the internet as we know it today - the internet IS a mashup on several levels, culture is mashups, and internet is today a very large part of how we expand and build our culture.
If the CEOs of said media conglomerates do know this (I suspect they might not, but I don't actually know jack), I can only assume that they're aiming to be our only source of culture - a futile (not to mention dangerous for themselves) aim if the public realises it.
I do not aim to deprive these richmen of further riches, but they need to understand and work with their customers rather than against them.
Ahh. Gotcha.