I've been reviewing today the JBoss OSGI documentation and I've been really impressed. They can work with existing containers such as Equinox and Felix but can do well on its own too. Check the documentation - it is very well written.
For some of you a 'new kid on the block' may not sound right if you've worked with or heard of JBossOsgi already :-).
It's likely to affect the existing balance on the market of OSGI-aware frameworks. Watch this space.