The older you are, the smaller your dog should be.
It's asthetically correct, convenient and appropriate. How many times do you see a picture of Britney, Paris or any new Hollywood socialite with a tiny dog - and how disproportionate it really is.
Would anyone's 83 year old Grandmother suit a Rottweiler or German Shepard?
The build of your dog should suit the owner, surely. Hmmm, then perhaps Paris is spot-on with her little pet. Damn, I flawed my theory.