I'll just try to describe where I'm coming from since we seem to be coming from different directions, so to speak.
...
I've listed below the issues that are important to me in the form of 6 guidelines which I hope might be helpful to others.
Ray,
I like your idea of setting personal selection criteria for a camera or photographic system, and also like many of your criteria, disagreeing mainly with elements that imply making a very long term or even life-time choice. So here is my slightly more "short-sighted" version. Order is vaguely indicative of importance, and realistically, item 1 takes absolute priority!
(1) Cost, based on an annual expenditure/depreciation allowance This includes the losses involved in replacing existing equipment if the choice is a new, incompatable system.
(Note: I expect current DSLR's to have life spans only comparable to laptop computers, after which either some of the fancy electronics will probably wear out or I will not be able to resist upgrading; thus I figure 20-25% per annum depreciation; film bodies and good lenses typically have far lower depreciation rates.)
(2) System image quality achievable, again within the scope of differences that are visibly significant with the print sizes and viewing conditions that I am likely to use in the short term, or have some significant probability of using in the longer term.
(Note: In the low probability of a radical and unforseen change in my photographic aspirations, I would do what I have done several times before; change systems: I will not significantly hamper either my current photography or my bank balance for the sake of hypothetical compatibility with very unlikely future needs.)
(3) Range and quality of lenses and accessories, within the scope of what I am likely to afford and use in the short term, or have some significant probability of buying in the longer term.
(See note above!)
(4) Weight, bulk, general handling, build quality and other features of a more professional nature.
(5) Company reputation for supporting the needs of my style of photography.
Assuming only that you are not greatly bothered by the lack of a standard zoom lens for Canon's 1.6x "APS" format that comes anywhere close in zoom range to their 28-105, 28-135 or 24-85 for 35mm format, I expect that my criteria will easily vindicate your choice to stay with Canon. For my purposes as a happy Canon film SLR owner, they are just two or three lenses away from a very good ranking; but for now, the 4/3 system comes out on top, with the Nikon mount system (including Fuji and Kodak body offerings) in second place, due partly to Nikon's pricy but impressive DX lens program. Current fixed lens cameras, even quite impressive ones like the Sony 828, and even assuming a few supplementary lenses, probably fall well short for both of us.