I'm asking about this because most companies that make revenues of a million plus and are in need of an integrated portal are going to go with Weblogic or something else. I'm a fan of JBoss, but when it comes to portals (which are very useful to enterprise customers) Weblogic has JBoss beat.
I have found it super easy to add new plugable modules into nukes. The source code has easy to follow examples, eg: Journal is probably the simplest. Don't bother with the tutorial as the last I checked it was very out of date. As the API has changed from RC1.
I suppose the biggest advantage to using nukes overjsr 168 is cost and maybe speed? Hopefully one day nukes will be 168 compliant, but you have to remember that it is only at version 1.