This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
Google Guice is really only a DI framework where the Spring suite of projects encapsulates much more. If DI is all you need then I guess evaluate both. I have always used Spring so I cannot make an educated comparison however Guice has a comparison on their website here: