The main difference (IMO) is you can use your model objects (i.e. Hibernate POJOs) in your view with WebWork. With Struts you have to use ActionForms. Struts has better client-side validation support, but WebWork's validation is more full-featured in its expression syntax.
If you want to compare the code needed to develop in Struts vs. WebWork - you could take a look at
AppFuse, which has options for using Struts or WebWork (or Spring MVC) as your web framework.
Matt<br /> <br />Author: <a href="http://springlive.com" target="_blank" rel="nofollow">Spring Live</a> and <a href="http://www.apress.com/book/bookDisplay.html?bID=256" target="_blank" rel="nofollow">Pro JSP</a><br />Weblogs: <a href="http://raibledesigns.com" target="_blank" rel="nofollow">Raible Designs</a> <a href="http://jroller.com/page/raible" target="_blank" rel="nofollow">Spring Live Blog</a>