Is this even possible? I will never use like 90% of them and I'd like to hide them.
Update: With the new update from Apple (v1.2), it is now possible to remove icons that you don't use, and to change the size of the icons. Under Settings->General->Home Screen you can show/hide individual icons.
I don't believe that you can delete the icons. You can rearrange them. I moved the ones I'm not interested in to the last screens so they are mostly out of the way.
The User Guide explains how to do this.
Based off experience with the iPhone and iPod touch I am guessing that the default apps are not deletable. the one app that can be hidden is the Nike running app that is turned on and off in the settings menu.
You can't, you can only remove them from your home screen.
It's simple. Go to Settings < General < Home Screen and then you'll see a menu with on/off buttons.
"Off" means that the icon won't show on the home screen and "On" means it will. Simply change the icon you don't want on your home screen to "off" and you're done.