Take a look at the Canon S95, Panasonic DMC-LX5, and Nikon P7000, all pocket-size and offering the kind of IQ you are looking for. Reviewed at http://www.dpreview.com/reviews/Q42010highendcompactgroup/
I have been happily using the Canon S90, predecessor of the S95, while hiking, biking, and skiing since late 2009. IMO it is the closest thing to a DSLR in your pocket yet made. I shoot RAW exclusively and run the Canon RAW converter in my netbook when on the road. Slower than the big desktop at home, but OK. The most time-consuming part of the workflow can be done in batch while I change for dinner.
The S95 lacks an optical viewfinder and a hot shoe, both of which you can get on the G12 at more weight. Their sensors are identical, and their IQ are both excellent, as the review indicates.