Unless speed at the expense of IQ and control is your only priority, jpeg on a DSLR is a pointless option.
I usually put it like this: if you shoot jpeg you start with as much image "information" as you end up with if you shoot Raw and convert the files yourself.
I'll say this too: there's not an in-camera jpeg engine in existence that can process a Raw file as well as I can, and there never will be.
Not necessarily, a few wedding photogs mentioned with the 5d3, they shot jpeg to sd and raw to cf, and took out the sd and plugged it into a monitor/laptop/etc to display ceremony pictures during the reception... One of my clients whom I shoot product photography, their catalog photos get saved at 1200x900 pixels and then resized down the 640x480 for web from there and usually they expect a few hour turnaround per batch of photos... jpeg for that is more information than they can even use for those applications. Every month we do printed publications in which Raw+jpeg are used for print and web purposes... I also have other clients that are nationally known companies, their photos are resized once again down to 640x480... I can shoot raw but in the end, photos are not going to be any better than a jpeg shot correctly in those applications, and quicker and for what it is, the companies couldn't be happier. In the professional arena we got to weigh time spent shooting, time spent post production, money charged per shoot and gauging how much work is needed to pull each shoot off... Ideally RAW is the best medium for everything, but business wise, sometimes it is, sometimes it's not. Doesn't make it right or wrong, it is what it is.