Eclipse have a ‘WebTools’ project underway on their site, to develop and add tools to support JSP, Struts, and other J2EE technology (EJBs, Web Services) within the Eclipse environment.
Depending on the quality and success of these plugins, I wonder if IBM’s Websphere Studio Application Developer (built on Eclipse and already offering these features) will take a hit when a similar toolset for Eclipse becomes available for free (of course you won’t get the integrated test Websphere server that you do with WSAD, which if you are targeting that platform is its major plus point)