This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
They're really quite different. General JSP and Servlet work would probably be as useful as knowing Struts 1. As Joachim says, Struts 2 is easier to work with than Struts 1. There's a lot less work just for the framework's sake. Of course, that comes at a price: not a lot of your Struts 1 knowledge is going to translate.