Have you seen the "Premium Compact" group test on DPReview....
Premium Camera Group Test (Q4 2008) Review: 1. Introduction: Digital Photography Review
The Canon and Fuji are included in that test. According to the data sheet at the bottom of the first page the Fuji has a *much* larger sensor - 1/1.6" vs 1/2.3" for the Canon.
Both cameras come top of the class in the test in good light, low light and with flash. The Fuji just edges out the Canon at the finishing post. I'm sure either camera delivers great results (for a compact) so you're unlikey to go wrong, whichever you choose.
The Panasonic is a different beast completely, giving you that extra zoom range, but perhaps at the expense of ultimate image quality at mid to high ISOs. The TZ5 is part of another recent group test on DPReview....
Prosumer Camera Group Test Q4 2008 Review: 1. Introduction: Digital Photography Review
where it earns itself a "Highly Recommended" award, beaten to first post by the far more expensive LX3.
If low light/high ISO performance is important to you then I think the results in these test report pages are very telling - the Fuji trounces the competition in the "Under £200" price bracket.
Fuji F100fd & Canon SD870 IS....
Premium Camera Group Test (Q4 2008) Review: 11. Real world comparison: Digital Photography Review
Panasonic TZ5
Prosumer Camera Group Test Q4 2008 Review: 12. Real world comparison: Digital Photography Review
Now I'm a big fan of Canon, having four of their DSLRs and a whole bunch of lenses, flash guns etc.. As I said earlier, I did initially buy the G10, but realised I would not make he most of its features and I was really going to be throwing money away. The F100fd and SD870 IS were top of my list and, for me, the Fuji edged it on price and overall IQ. If you're a fashion victim you may struggle to resist the Canon.
One neat feature of the Fuji is the option to take pictures in pairs, one without flash and one with, and then decide which turned out better. Here is an example, not great by any means, but just to show how different shots can be with/without flash....
This was taken using available light only. I've increased exposure by +1 in Lightroom but there are no other edits. EXIF for this is 20mm, 1/25, f/4.5, 1600 ISO. Note how the ambient light from the background has been included in the exposure.
[IMGLINK]http://lh5.ggpht.com/_4_R8TkwT74w/SXm4eMKrmfI/AAAAAAAA9_w/dyX1Ly6T-t4/s800/20090117_082900_0054_LR.jpg[/IMGLINK]
Here's the matched photo, taken less than a second later, with flash. See how the flash has illuminated the subject but the background is lost. Personally I prefer the first image, which needs some colour tweaking, but has better overall appeal. EXIF for the second shot is 20mm, 1/100, f/4.5, 800 ISO. This has also had +1 added to the exposure in Lightroom.
[IMGLINK]http://lh5.ggpht.com/_4_R8TkwT74w/SXm4e48oLdI/AAAAAAAA9_4/L9-GHUBRuLo/s800/20090117_082901_0055_LR.jpg[/IMGLINK]