I had never had a strong position on this until now. I was actually in a White House meeting (technology was part of my portfolio) that could have shaped how the FCC would regulate net neutrality, but didn't have an opinion at the time.
I saw a statistic today that helped me finally decide my position on Net Neutrality. In Time magazine, Dec 10, 2007, on their Numbers page, they cite a PCWorld article which says that by 2010 the Internet could slow to a crawl due to exponential demand growth for video, and that needed Infrastructure will cost $137 billion. Or over $1000 per US household. Of course these numbers are likely flawed, but still illustrate the danger of not having pricing on the Internet.
Those who advocate for Net Neutrality advocate a system like our airports or our highways, where the law prohibits most attempts to regulate who uses them. This is good for giving people free non-disriminatory access. It is very bad for controlling congestion. As highway traffic and airport delays get out of control, we see the dangers.
Similarly for the internet, if we had a pricing system, that would provide the funding necessary to pay for upgrades, and minimize the congestion so that people watching stupid youtube videos and porn movies don't block all the other low bandwidth stuff that may be more productive. Of course if people are willing to pay more per kB transferred for those porn videos, then they should be entitled, a pricing system allows the system to allocate to the most productive use. But still, for the price of 1GB video, you'd be able to receive several years worth of e-mail. The Internet Net could still be effectively free for most uses.