I've been a G9/G10 user for some time, always wanting to make sure I had a decent camera with me. I realized out of all of my G10 shots the best I ever did with them was some small prints and a some web images. The entire purpose of carrying the camera around was to get enough quality so I could actually make a decent size print even if I had to do a little cropping, and certainly some of the images were OK, but what I found myself doing was hauling the Canon system to places because I didn't think the G10 was quite good enough. I would like the camera to be adequate enough for circumstances that I know I have a chance of getting a good image when doing an activity that is difficult to haul around a larger system ( for example playing golf at Poipu, Kauii). Just having it in my pocket didn't do any good if the image just didn't cut it.
Sort of like that new book touting the iPhone camera .."the Best Camera is the one that's with you" ... well if an iPhone is good enough fine but just taking an image is only part of the story ... if it looks pretty good but all you can do with it is put it on your blog ... well not what I'm interested in. You can always change that formula by finding a way to have a better camera with you. I'm not saying you can't take great images with a G10 or S90, or an iPhone for that matter ... I just don't like being that limited in what I could do with those images.
So I just took delivery of a GF1 system with 20mm/1.7, 14-45 zoom and the EVF. First impressions .. wow, what an awesome little camera. With the 20mm on it it's barely larger than the G10, but the picture quality is much better.
Guess time will tell, but right now I"m pretty excited about this as an option vs. the G10. I certainly will feel better about having it along as another option when out using my MF gear.