Well, Wizards did make a few adjustments and clarifications. Some rules that were messy were cleaned up, some added, and character classes were adjusted to clarify that class's role in the world.
For those interested and haven't seen, I've included some links that explain some of the changes and what not.
Info found on pages 300-301 of the DMG
Haste revised
DMG Table of Contents
Author notes on class adjustments
