One of worst part of Spring billions configurations, even in Spring3 you must have config files... For example you have SOAP web service and want to integrate Spring as backend.. and you can find what you can not inject Spring beans in regular web service.. and you must change also your services to Spring SOAP.....
Spring3 used annotations, but it is annoyed you every time to guess which annotation to use for opening or closing some services....
Instead you can have just EJB3.1 which is power, simple and as java developer you can just enjoy it.
I noticed what a lot of Spring fans do not know EJB3 anymore, whats why they like Spring:)))