One of the things that hasn't been mentioned in this thread is "handling". This is the way a camera responds to your operations.
Until recently, my only camera was Nikon FM2n, with motor drive, 35-105 and an 80-200 f4 Nikkors. Although this is a fully manual SLR, one of the main reasons I like it because it feels and handles right to me. For example, there was minimal delay between pressing the shutter and the actual exposure (shutter lag). So even when I did weddings and sports, I could freeze what I wanted. The switches are durable, so I can jam them without fear they will fall off.
Early this year, we got a cheap Canon A540 point and shoot camera. At first I liked the small size and light weight, compared to my FM2n that was rather heavy. I liked that fact that I could shoot as much as I wanted without worrying about running out of film or processing bills. And its so compact that even my wife, who is rather petite, and a technophobe to boot, has no problem with it. But on my first sports coverage (UAAP tennis 2007), I struggled with the handling. The focusing was slow, and the shutter lag was considerable. Pre-focusing didn't help much, neither did changing the aperture or speed priorities. It also could not recover fast enough to get a series of shots, unlike my SLR which could go 4 frames-per-second all day (as long as it has enough film). The surprising part was that the small size of the body became a problem because I have big fingers, so it was hard to get to some buttons. And the build quality is nowhere near my FM2n, as I sometimes fear the A540 might fall apart in my hands in the heat of a shoot.
Lat week I tried a friends DLSR (Pentax k100d). It is head and shoulders more responsive than a point-and-shoot, and the build quality is better.
My digital point and shoot is great for small events and tourist-y moments when I just plan to take snapshots and don't want to carry a bag of gear. But for events like weddings, sports, and serious stuff that demands responsive handling and control, there's nothing like a SLR, film or digital.