[starkfist]

You have to be too close to the face in order to throw out the background with a 20mm 1.9. It's going to make the nose look weird and accentuate a double chin, if you have one. (I have the same camera and lens)

[j00lz]

I get great results from using that lens for portraits. The 20mm lens is really a 40mm due to the x2 cropped sensor in m4/3 cameras.

[jonah]

40mm equiv. is too wide for portraiture. typically you use around an 85mm lens. this would work out to 40-50mm in micro four thirds.