I received similar kind of comments regarding JSF, from quite a few folks. Actually, yes its a bit different from usually web frameworks. You need get around it. When I first worked with JSF, I found it fascinating. I believe, once you get it right, it would become pretty straight forward.
Struts was the thing of past, haven't looked into Struts 2. Never feel like I need to.
Struts is simpler because it does nothing. Seriously, all Struts does it cause you more work than you had to do before. I guarantee you that it is less work to write servlets or plain JSP than it is to use Struts.
Seam gives you so many integrations that you feel like a kid in a toy store. Email, PDF, charting, Excel, RSS, JMS, async/timers, BPM, security, CRUD framework, persistence management, Ajax remoting, REST integration, and the list just keeps going on and on. Struts just sits idly by.
JSF is a new paradigm for Struts developers, yet not so new. If you compare JSF to the HTML tag libraries in Struts, then you see that you get the exact same thing (the ActionForms) but it works so much better because JSF has real converters, validators, and thread-safe bindings (Actions in Struts are shared). The FUD about JSF was probably true before Seam, but Seam just silences all of those voices and what you realize is that it is just a waste to try to avoid JSF at this point, especially if you are coming from Struts.
Struts is simpler! It was long back when I first tried it and wasn't too excited about it. I looked at JSF only recently and it makes everything looks so easy... there is no going back. I do hope that they make JSF pages bookmarkable or maybe that is something Seam already has...