Just picked up the new H&Y Magnetic Filter Holder for the M.Zuiko 7-14mm F2.8 from PhotoSphere.Sg in Singapore. This product is so simple, you wondered why nobody has ever done this before.
The holder is all metallic and fit perfectly to the lens by using a clamp with foam gasket around and in the front, there are four teeth that will go into the petal lens hood of the lens.
If you already have a 100mm filter system, you can use your existing filters by just putting the magnetic frame around your filters.
To use the filter you just put it onto the holder. Technically, you can stack as many filters as you want, however, for the 7-14mm I was able to use it up to 3 filters without any vignette. Furthermore, when you are using a graduated filter you can turn the filter up to about 40º and still not get any vignette.