A number of folk asked to see the (opening agapantha after it had opened, and I was planning to post an image with more of them in the background, but this turned out to be an interesting subject with which to compare cameras.
To start with, I have to say that the comparison is not exactly a 100% true comparison. The 40D image is the result of a jpg converted from a RAW image, while the S90 image has been converted from a tif file (Adobe's DNG converter doesn't yet cater for the S90 RAW image).
What I have found, though, is that the S90 produces a better image (virtually 100% of the time, if one underexposes by about half a stop). There is also a very significant difference between the two cameras, which I will expand on a bit later.
So here are the two images. I'm not going to ask you to decide which is from which camera (though you are obviously welcome to have a stab at it if you would like to), but would just like you to say which one you prefer - top or bottom image.
All images © Rob Minter, and licensed in terms of a Creative Commons Attribution-Share Alike 2.5 South Africa License