I like Wayland, but I avoid using it because (last I checked) a crashing or killed compositor takes the whole desktop down with it. Meanwhile, under X I can restart Gnome Shell (or equivalent) if it's having trouble due to a memory leak or the like. Crashes and memory leaks have been common enough that I don't want to risk losing work to them just for some minor benefits.

This isn't an intrinsic problem with Wayland—I'm just not aware of anyone making a compositor that can recover or restart yet. I'll be excited to try out any that people write.