The internet is for whatever we want it to be. What is on the internet will be a reflection of what the users want, and sex only makes up a slice of our lives. For most of us, it doesn't dominate it (or at least, it shouldn't).
A lot of the internet is used for economic transactions, business purposes, pure communication and data monitoring, storing, collecting. Thanks to cloud-computing, scientists are using the processing power of multiple PC's to figure out how proteins fold together or to look for splicing patterns and regulatory sequences. That's not porn, and I can tell you, scientists are running a LOT of calculations.
Maybe porn makes up most of the internet that the average male user visits, but when you take into account the internet as a whole.... man, 1.1% sounds about right. There's a lot of places on the internet that most mainstream audiences will never visit - pubmed or the ncbi for instance - huge, enormous biological/genetics information databases that most people have never heard of.
Google is making a cracking effort at trying to catalogue and store almost every single bit of print in the 20th century. If you've seen how many books and magazines they've scanned in, that alone probably surpasses the amount of porn on the net.
And what about stock information or the data streams coming from satellites, or the amount of forum posts or the amount of gaming information....
yeah, if you think about it, 1.1% sounds about right.