Well, spent a couple of hours testing out the GF1, and I am very, very impressed. Negatives: less comfortable to hold than a small DSLR, rather loud shutter, no focus confirm beep for legacy lenses, RAW files are rather dull by default (I will create a new profile in Lightroom once I've got more samples), focus magnification for legacy lenses requires two keypresses instead of just one. Positives: compact, fast, versatile, good IQ, and this legacy lenses thing is so fun I can barely stand it (as many G1 enthusiasts have said, manual focus is as easy as on a Leica, and perhaps more precise, ultimately). Also, I've got the 20mm f/1.7, and it is awesome, and aufofocus is blazing quick...plus, it focuses WAY closer than any RF lens and most SLR lenses as well. I'll probably get the EVF eventually, but I had no trouble using the screen...I do not share many RFFers' disdain for composing on an LCD, even if I do prefer working at eye level.
Some sample pics with various lenses are below. My favorite to use so far is the Olympus Pen 40/1.4...it focuses very close...and looks great on the camera. I will have to save up for the 60/1.5!
Panasonic 20/1.7 at 1.7:
Nokton 50/1.1 at 1.1:
Canon 35/1.8 at 1.8:
Olympus Pen 40/1.4 at 1.4: