I have an Exslim and really like it. I carry it in my briefcase on business trips in case I see something I want to take a picture of. The only downside to the Exslim is that it does not have a viewfinder - but the anti-shake program is good. My other camera is a 20D.
My daughter wanted an ultra compact and, based on research, I had decided on the Fuji 11. Once I saw and tried it, though, I knew it would not fit her needs. It is just too bulky and heavy for what she wanted, even though it apparently takes great photos. Instead, I bought the Ixus 55. She absolutely loves the size and the quality of pictures. She also has a Canon 30 slr, so knows something about picture quality.