Well, we now have another reason to support a 2nd engine for the JSF, it appears that the GE/Rolls-Royce F-136 alternate engine will be the first production engine to use ceramic composites. (paid subscription required)

Right now, they are looking at using it on stationary parts of the engine, “vanes, shrouds, combustor liners,” though there is investigations of using it on rotating parts too.

There is both a significant weight savings (Nickel is heavy), and a reduction and/or elimination of the need for cooling air.