Sure, Micro Four Thirds has a smaller sensor, and the appearant DOF of a lens is as if it were two stops slower. Thus my f2.8 looks like your f5.6 (at least if you use a 35mm sensor), but that does not mean that my f2.8 does not gather as much light as yours. It may capture less light, but it concentrates it on a smaller sensor area. Light density is the same and so are my shutter speeds for the same exposure value as yours. It’s only that my lenses are smaller and lighter 🙂
And if I really crave for very shallow DOF? Well, depth of field depends at least as much on subject distance as it depends on aperture. These images have been taken at f2.8, but due to the lens’ great close-focusing capability, I can just go a little closer.
You probably know the effect best from macro lenses: once you get close enough, DOF is shallow even at small apertures.
Now, with shallow DOF clearly achieveable, bokeh is the important factor. Do the out-of-focus areas look good? Creamy? Soft? The Image of the Day is obviously as creamy as it gets. Out-of-focus highlights from the droplets are even discs with no obvious borders or onion rings, and even the second image looks pleasing to me. Its abundance of hard lines at all background distances is more or less a torture test for bokeh, and I’d say this lens behaves quite well.
The Song of the Day is “Summer Grass” by Kiyoshi Yoshida. Hear it on YouTube.