Weber was saying for the YEARS that they would NEVER make a 22" WSM, even just a few weeks before they started leaking the announcement of the 22" WSM.
That doesn't mean they will make a ceramic, but it does mean that they keep things under wraps really well, and nobody can say for sure what they are going to do until just shortly before something is announced.
I don't see a need for them to enter that market, personally. However, these things are clearly not just a "trend".
Your guess is as good as anyone's, really.