Decimate modifier; "Convert to Multi-Res"

Sometimes you're sculpting a mesh in one app, and you want to bring it into Blender for further work. If you want multiple subdivision levels maintained, you have to use the multi-res modifier with the shrink wrap modifier, which can be inaccurate at times.

The Decimate modifier has an 'Un-Subdivide' option which does a pretty good job of reconstructing subdivisions as Zbrush does. It's a shame that you cannot simply transfer the vertex information into the multires since it's using the exact same geometry. Instead, you'd use the shrink wrap modifier and sometimes not get the right result.

I think it'd be very handy to have a button you can click that converts the decimate modifier into a multires via the 'Un-Subdivide' tab. If we have that, and some good work is done on the Un-Subdivide process, I think Blender will take a big step towards replacing the need for Zbrush for the average user.