I can only think of two specific things:  lack of official support, and lack of patches/updates.

The forums can be a great source of help and information, but it's a volunteer community, and you may not get an answer if you have problems.  Having said that, there are several very knowledgeable and helpful people here.

Patches for functionality or security issues are also generally not issued for individual Wildfly releases.  You are able to pull the source code updates and build your own artifacts if you desire.  Otherwise, you'll need to wait for the next Wildfly release for updates of that sort.  Wildfly currently releases on a quaterly schedule.