Like my previous post, I will try and keep this also a *living* post i.e., I will keep updating it as and when possible.
JBoss is written with JSR 168 in mind. However, it can only be installed on Jboss application server. With an open source product, I would have thought vendor-lockin to be the least of all issues!! There are a few out-of-box portlets like User and Role portlet, CMS and AdminCMS Portlets, Permissions portlet and a Forums portlet. The CMS features are very minimal. I am not even sure why they call it a CMS portlet because all that one can do is create html pages using a rich text editor and do some file manipulation activities (create directory, move and copy files and so on). My feeling is that instead of a sophisticated portal server, JBoss aims to provide a robust JSR 168 portlet container that takes advantage of possibly the best known open source application server. Nothing wrong with that approach though.
Liferay on the other hand can run on any servlet container, starting from Tomcat to full application servers like BEA and JBoss. It is JSR 168 compliant and has a large number of sample portlets. The CMS portlet is more feature rich than that of JBoss in the sense that one can create custom content types and own templates. This helps separate content form its presentation. It is also very easy to create new pages and add them automatically to the navigation bar.
Updated July 27, 2005
Liferay announced release of version 3.5. There is a review here. There are some new themes and cool features. The one i liked are the navigation portlet and the fact that there can be multiple instances of same portlet. The navigation portlet is very useful for us because it helps me create a multi-level navigation menu very *easily*.
Updated Aug 01, 2005
There is an excellent review of Liferay 3.5 here
Updated Aug 19, 2005
Liferay has released version 3.6. It has a cool drag and drop using which one can position portlets into different areas of the layout.