If they do drop support, I suggest switching to Bricolage...
I hate to say it, but that is kinda my opinion also ... Bricolage I've
heard alot about ... never heard of WebGUI :(
I haven't heard of any of them and probably won't use them either but
deciding solely on web sites I'd choose WebGUI. Screenshots of WebGUI
are more attracktive than screenshots of Bricolage (look does matter),
WebGUI's website looks slicker and they claim several fortune 500
companies using their product and they have a big list of (all?)
companies using their product.
The point being: if you want many people to use your product you have
to pay attention to marketing. At the very least have a decent web site!