Shoot raw!

[neonlamp]

Ian's comments on his considerations for JPEG over raw did not mention one other important aspect of shooting raw. The basic problem from my point of view is that our eyes respond to light in a logarithmic manner, but digital images only see with a linear response. Therefore, we can actually perceive the world in a range of light and dark more acutely than digital sensors. So taking pictures in bright daylight, which of course is usually discouraged because of the harshness, but sometimes cannot be avoided, gives darker shadows and blown highlights if not careful. Much of the shadows and highlights can be recovered in DPP, Canon's free processing software, and that can make the difference between a dull sky and one with distinct clouds or tints of blue, or bring out the shadows - or even darken them if objects in the shadows distract.
Many other features are available to adjust images in DPP which do not work on JPEGs. My preference, and recommendation, is to shoot raw!

[El Sid]

Raw is my format of choice, mostly because I have a terrible tendency to forget to reset the camera if I've used unusual settings, eg I set the camera to mono and forget to turn it back - at least with raw I can get the colour option back in post...

About the only time I use JPEG is when using the motordrive function as JPEGS consume far less memory and burst depth is much greater.

JPEG can still produce a decent result for those who have the discipline to check their settings regularly (as well as a functioning brain cell that remembers to do so...).