it can produce a blur but you've got to be close to you subject. Remember its a wide angle and that'll put a lot in focus.

Here are a couple of shoots I've taken that I like and like the blur:

http://www.pbase.com/image/23823268

http://www.pbase.com/image/23936904

Although mind both of these shoots were taken at 40mm

Hope this helps you a bit.

Scott