One feature you might not have heard of between the headline acts of FireMonkey, LiveBindings, VCL Styles, 64 Compilation and Mobile Connectors is a fantastic update for documentation.
In Delphi XE2 you now have Documentation Insight Express - a great tool (available under the Tools menu) that allows you to document your code as you go.
Document express uses XML to leave comments in your code that are then available alongside code completion. VERY handy for sharing your work around teams, or as a good reminder when you come back to a project after a few days, weeks or years!
This short video shows you how to get started and demos what happens when you put values in the different documentation nodes.