Strange when I start working with layers I assume I'm going to need to flatten the image and look in the layers menu. But that's becuaee I've used Photoshop and I can see the other point of view.
So how about the compromise of leaving the option in the Image menu, but adding a button to the layers palette.
It would require a "Are you sure...." confirmation dialog in case users hit it by mistake.
A mention in the layers section of help would be great.