This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
If you are using Struts 1.2, ActionErrors is deprcated and you should always use ActionMessages. If you are using Struts 1.1, use ActionMessages for informational messages and ActionErrors for error messages.