Dpreview just posted the Ricoh GXR review.
They compared the camera with the Panasonic GF1. Use this quick links to see the results:
Ricoh GXR vs Panasonic GF1 noise test: http://www.dpreview.com/reviews/ricohgxra12/page15.asp
Ricoh GXR vs Panasonic GF1 JPG test: http://www.dpreview.com/reviews/ricohgxra12/page24.asp
Ricoh GXR vs Panasonic GF1 RAW test: http://www.dpreview.com/reviews/ricohgxra12/page28.asp
Ricoh GXR vs Panasonic GF1 High ISO: http://www.dpreview.com/reviews/ricohgxra12/page29.asp
Ricoh GXR vs Panasonic GF1 Resolution: http://www.dpreview.com/reviews/ricohgxra12/page30.asp
Reminder: the Ricoh GRX is a modular camera. If you buy every single piece on Amazon you will have to spend quite a lot 🙁.