OSGi brings new techniques like versioning and its service model to the Java space. But like any new technology, its important to realize where its limits are. This post by Erick Newcomer contains his "Not List" on Enterprise OSGi.
Enterprise OSGi is not: * Java EE - but EE components are being mapped to OSGi * A new distributed computing stack - but it defines how to use existing ones * Spring - but it has a "Spring-inspired" Blueprint service that does something similar * Something a bunch of vendors dreamed up and decided to standardize - it's a grass roots effort started because people were already using OSGi for enterprise applications and needed help * Done - the release of the specification is scheduled for June/July (part 1) and December (Part 2) * Simply a deployment standard - the real power and ultimate benefits of OSGi are in its service programming model * Untested - the OSGi Framework has been successfully used in enterprise scale deployments
Read Erick Newcomer's entire post 'Enterprise OSGi - "Not List"': http://modualrit.blogspot.com/2009/03/enterprise-osgi-not-list.html