OneNote is one of those apps that kinda defies explanation and really requires you to try it for yourself - the best analogy I can think of is "digital notebook" - which usually makes people's eyes glaze over...  Until I show it to them - then it all starts to make sense ;-)  OneNote 12 will even include OCR so you can take a snapshot of the classic "DO NOT ERASE" whiteboard and have OneNote figure out what you wrote, digitize it, and make it searchable...  Definitely kicks some booty...

And if you register to grab the eval bits from https://microsoft.order-10.com/Onenotedl60day/welcome.aspx?id=tryonenoteNorthEast, you'll get entered into a drawing to win a Toyota Prius...  So you can be just like Cameron Diaz or any of these folks ;-)  Good luck!