I shoot RAW exclusively: I learned my lesson back when I was shooting film. I once shot an event using some cheap, outdated film because I intended to use the shots for an insignificant web project. Then, a few weeks after the event, I was asked to write an article about and provide photos for a regional magazine. The quality was certainly good enough for *them*, but they definitely looked substandard to *me* (and would to the people reading this list). Shooting JPEGs is like shooting with inexpensive film: It's usually good enough.
The extra latitude (in every sense of the word) afforded by shooting RAW more than makes up for the slow buffer issues with the ist-D and the conversion time is a non-issue with my workflow - I have an "automatic mode" that handles everything for me when I'm in a hurry. The difference between RAW and JPEG is certainly less than that between good, fresh film and cheap, old film, but I'd still rather shoot RAW mode and not need it than vice-versa because I've learned that sometimes a casual shot becomes a money shot after it's too late to change your mind.