This question is often asked, but tends to be answered by people who have a strong allegiance to Spring and tend to give a massive list of advantages, which often boil down to a much smaller list of actual advantages. I think the real advantages are:
1. Based on interfaces, not classes, so easier for your classes to inherit from your own classes.
2. Provides request interceptors that can do things to requests before or after your page controllers.
3. No form objects. Binds directly to your Hibernate POJOs, so you don’t have to convert between ActionForms and Hibernate POJOs.