A professional photographer who works in Hessle just outside of Hull told me the same thing a few weeks back. He just got a catalogue contract and got that because he doesn't sharpen everything so it pops. Supposedly a softer shot is far more preferred for portraits atm!
His words not mine
That is standard for any kind of professional stock photography. I sell some of my work through various micro and macro stock agencies and I will never sharpen any of my files for these agencies as it is up to the customer and the graphical designer to manipulate the image as they see fit. The same applies to conversion to black and white or large changes in exposure/saturation/contrast from a relative normal baseline. You never provide a B&W/low-sat/high-key photo, you provide a well exposed base image that graphical designers can work with.
Sharpening is an important processing step for the output of the photo and it depends on the output medium (web, vs TV vs small print vs large print, vs canvas). Sharpening is a requirement due to the Anti-aliasing filter in most cameras that soften edges and reduce micro-contrast.
What a1ex2001 was referring to was a psycho-physiological effect induced by the strong relative difference difference in sharpness and resolution between an out of focus background in a shallow DoF photo and the focused subject makes the focused subject appear much sharper than it actually is. this works if the subject is not critically sharp due to lens softness or focus errors, but something like handshake or motion blur will still be easily observed (the human eye is very sensitive to motion induced blur as a heuristic to measure egomotion and apparent motion in scenes, hence why classic photos of a blurred train speeding past a train track on a sunny day induce a feeling of motion).
So you still want to make sure shutter speeds are sufficient to reduce shake and subject motion blur, but you can sometimes get away with a slight miss-focus and lenses that are not particularly sharp wide open will usually look fine if the subject is still much sharper than the background. Of course that does not at all apply to things like architecture or landscapes where detail is very important.
