Save the Internet: Our Two Cents.
You can read in any number of places how the demise of network-neutrality will turn the internet (or, at least, the USAian portions) into yet another place where corporate interests can control the flow of information, determining what you can and can't see. The important thing here is that it doesn't have to be that way; this is far from a settled question. So if you're an American citizen, here's what to do:
Pay attention. Keep an eye on legislation regarding network neutrality. The EFF and other advocacy groups on the good-guy side can keep you informed. And when a bill comes up, like Senator Ted Stevens's Communications, Consumer's Choice, and Broadband Deployment Act, write to your sentators and congressmen. Write to them on paper. Do not email; that gets ignored. Tell them to preserve network neutrality. Remind them that the internet, as it stands, is the best thing to happen to free speech since the first ammendment, letting every voice be heard and letting messages spread on their own merits, not on the strength of who owns the presses and controls the distribution of books and papers. Point out that the rest of the world is keeping their portions of the net free and equal; can we, who claim to love freedom of speech so much, do any less? Tell your elected representatives to stand up for the principles we should all stand for.