I have and use a Canon G9.

The final image quality is excelent,  I cannot find fault with it . 
What I like most about it is the build quality. It is a very solid little camera and feels good in the hand.  It has all the features which you would find on a non pro dslr.
Limitations - ocassionally the auto white balance is out in difficult artifificial lighting, it can shoot RAW though. The internal flash is not very powerful. It does not have a tilt/swivel lcd screen like my older G6 had.  It is not a lightweight as far as compact cameras go.
Other people when they see/use it always comment on how solid it feels and the picture quality.  
There is a new Canon G10 coming out now. 

The panorama image of Greenwich in my gallery was shot on the G9,  using the G9's auto panorama feature.

I cannot say how it performs against others as I don't have personal use of other compact cameras.

Ones to consider - I looked at a Panasonic G1 in a store the other day. It looks a fine little camera and has interchangeable lenses it uses the 4/3 system.   

And every one said, 'If we only live,
We too will go to sea in a Sieve,---
To the hills of the Chankly Bore!'
Far and few, far and few, Are the lands where the Jumblies live;
Their heads are green, and their hands are blue, And they went to sea in a Sieve.

Edward Lear
http://www.nonsenselit.org/Lear/ns/jumblies.html