The problem with the REST plugin is that if you use it, then you have to use it for all actions. That is not feasible for those who already have applications running on struts 2. It also doesn't solve all your problems.... like how to have a folder like structure for the urls?
With the
convention plugin in struts 2.1 you can create seo friendly urls without the annoying .action suffix. The only problem is that you can't create hierarchical urls. But there's a way around it. If you look at
http://www.visualmandarin.com you can see that we have hierarchical urls and we are using struts 2.1 and convention plugin. I explain in my blog how to do it:
http://simplyolaf.blogspot.com/2009/06/creating-hierarchical-actions-in-struts.html