Point me to your previous posts. I wasn't able to find any of them.
Yes it's the best jboss forum as it's the only one now that we develop. However, here we still use nukes and we are in process of moving to JBoss Forums soon.
Comparing to implementations from other companies is quite hard because none of them are portlets (I don't know any). So, this would be a good summary of this comparison, JBoss Forums at this point is only suitable for use with JBoss Portal while all other are not JSR-168 compilants.
JBoss Forums Lead
JBoss Labs Team