That's true about:
Spring is a lightweight framework requiring just a web container.
But in most part of the time, you'll see something different. You'll see Spring projects using the same application server that could be used by EJB, that's why everyone wants to enjoy the nice built-in features they offer, and when you use a web container with Spring, it will probably use the same or even less services than an analogous EJB project on top of a lite container.
I really like Spring, but is difficult to say which one is best. And I'll not start to state the benefits of EJB or Spring because this discussion already exists in a lot of places. The tip I can give anyone that wants write a project must think not just on the technology itself, but also on the team that's gonna use it, with all this in mind, you'll surely make the right decision!

Feel free to ask me anything!
www.BlackBeltFactory.com/ui#!/ref=jmotta, SCJP 6, OCWCD JEE5, OCE EJB JEE6