Best m43 as of mid 2012

I'd like to add a small and lightweight camera to my collection. I own a Nikon D7000 together with a couple of lenses and I like it. Sometimes though I have the impression that it just takes too much space and weight in my daypack when I am on a mountain hike / climbing tour / skitour and I leave it at home. I then take my small camera with me which basically works fine, a Canon S95. Yet sometimes I miss the image quality and dynamic range of a large sensor. Therefore I think about something in between and thought about a m43. My main criteria for that camera:

• (small) size and weight

• image quality and also lowlight performance

• hdr (ae bracketing toghether with continuous shooting)

• quality zoom lens(es)

• fast autofocus

• some manual control like aperture / + - / autofocus points

• raw files

criteria i don't care that much: (electronic) viewfinder, megapixel count, scene modes, ...