I could never have your job, if there's one thing I HATE it's running errands in a hurry, in the city, by car. In fact, within the inner city travelling by bike is faster here. Not to mention more flexible as you can use walkways and paths if you need to, and a lot less stressful. (But that may have something to with that I'm about 100 times better at riding a bike than driving a car )
But bike messengers do vastly outnumber car messengers here.

Cool article, btw!