Note: See also a related article I wrote for TechTarget.com.
I've been updating my workbooks to OpenOffice.org 2.0. One of the big differences is the look and feel, i.e. the toolbars. They have different icons to show you how to see the whole toolbar, and you view them differently.
It's not hard, but it's definitely different than 1.x. So here's an excerpt from my OpenOffice.org 2.0 Core Office Suite workbook that describes how to do a bunch of stuff with the new toolbar system.