Got mine two days ago, and have been enjoying it since.
My thoughts so far:
1. Build quality is just a little better than the 20/1.7. Manual focus ring (although fly by wire) feels better dampened.
2. Probably just as sharp as the 20/1.7 (which is still a great lens), but tonality is much smoother. Bokeh a little smoother too.
3. Looks really nice in the deep black (albeit plastic) finish. I think it looks awesome mounted on the OM-D. 😎
4. The lens hood looks ridiculous. 😱
5. AF seems faster than the 20/1.7 on the OM-D.
Although I don't regret buying it, the only reason I bought is because my wife refuses to lend me here 20/1.7 for extended periods of time. 😀 Since I didn't want to have two identical lenses at home, I went for the PanaLeica.
Some samples from the past two days: