LIberty Profile support is in plan for the current release under development. You can look at the CLM 601 release plan or the release plan for any of the products.

My understanding is that the main changes around Liberty are:
- using Liberty as your application server is now supported,
- Liberty will come bundled with CLM, and
- Tomcat will no longer be bundled with CLM.  
So if you are currently using WAS, you will just keep using WAS, and if you are currently using Tomcat, you will need to decide whether to keep using Tomcat (which is supported) or switch to Liberty.