The importance of net neutrality has already been hashed out on the internet a thousand different times in a thousand different ways, but it is a cause that's worthy of repeating, here, once more.
What is net neutrality? Simply put, it prevents ISPs from discriminating against the content you demand.
Imagine the internet as a series of tubes. These tubes compose the entire internet infrastructure, and when you wish to retrieve something from the internet, you put a message in the tube, wait for it to get to its destination, and whoever is on the other side takes your message, finds what you're looking for, and sends the packet back down the tube, where it reaches you.
These tubes are built by the major ISPs, and so the ISPs charge you for sending messages down the tube, and charge you for receiving the package. They charge the people who send the packet back to you as well. They make money whenever anybody puts in or takes out anything from tube.
Now, you would think that they're being paid for the volume of your messages, rather than the content, they shouldn't care what you put into them. Video should be treated the same as text which should be the same as peer-to-peer networking. Fundamentally, they're all the same to the ISPs. They make the same amount of money, per packet, for each.
Back to the pipes. If you want a faster internet connection, you need a bigger pipe. Likewise, if you have a lot of people using the internet at once, you need a large pipe to accommodate said people. When ISPs sell you access to their pipes, they advertise how big their pipe is. 10, 50, 150mbps. The ability to shovel things into the pipe as fast as things come out of it. They advertise these things, but if you are an internet user, you know that they don't always deliver.
Oh, yes, they have excuses. They say "unusually large load" and "network congestion" and "it will be fixed quickly", but more recently , they're beginning to blame those who use their pipes the most. They claim that people are torrenting too much, so they have to slow down torrent speeds so that others can get a chance. They claim that that Netflix is clogging their pipes because they send so much video data, so that Netflix should pay them more in order to compensate for their traffic. But the truth isn't any of those things.
The truth is that the ISPs are overselling their networks. Overselling is a common occurrence, as building an infrastructure for the maximal load is prohibitively expensive compared to building an infrastructure for typical load. But the ISPs have either grossly underestimated the typical load, or they continue to advertise their maximum speeds even when the tubes are past their full capacity.
So now the ISPs are either slowing down certain content which they claim is congesting their network (even though you already paid for that content at normal speed), or attempting to charge more for the speed that you're already paying for. There is no fast lane; the fast lane isn't another tube that you're paying more for. The fast lane is the same tube, providing you with your content at the speed that you are already supposed to receive your content at, but they'll deliver it at the expense of all the other content in the tubes (and your wallet).
Now, if they changed their advertising so that the customer actually knows what they're paying for, and spent the money to attempt to improve their infrastructure, I would concede their point. But the ISPs don't even care to improve their infrastructure, taking money and lining their own pockets. Most ISPs have little to no competition in their areas, so there's no incentive to improve. They just keep driving up the prices because there's no other alternative for access to the internet.
So what would happen without net neutrality? The customer will pay increasingly higher prices to the ISPs for unusable connection speeds to most of the internet, while only having reasonable connections to content that has to be paid more for, on either end. No more innovation will occur on the internet, as it's impossible to compete when it's prohibitively expensive for startups to reach their consumers. The internet will become a walled garden, shut off from what it could have been.
And that's what I fear. I have been in the tubes since their earliest days, and seen it change from an open sandbox to one dominated by cookie-cutter houses. Don't let them make it any worse.
Or I'll go out and make my own.