I have the G9 and G11, and prefer the handling of the G11 because of the swivel LCD. I also have the A620 with a swivel LCD, and prefer that feature. I have used my G9 a few times since I got the G11, and find it more difficult to use because the LCD is fixed. I didn't think that about it for the past two years I've used it, but now that I'm back to using the swivel LCD, I find I "need" it. The G11 image is also excellent, even compared to my G9 at ISO80. The G11 handling is not perfect, since I occasionally press the Menu or Function button without trying. However, it's not a deal-breaker for me. I never got Richard Franiec's Grip for the G9, which many felt was a MUST have addition.
I mainly kept the G9 for the longer zoom, and to use with the Canon underwater case I have for it. However, I feel I may sell it and move on someday.
Dennis