Except for the fact that most people like to run on paved surfaces where you're going to rip up your feet and get a nail in your toe if you run bare foot. Running bare foot basically limits you to grassy areas in parks that are not also frequented by heroine users.
Local High-school track is ideal for barefoot running. I have been running barefoot for the last 3 years. My knees don't hurt anymore. The ground up rubber surface provides a bit of cushioning.
What kind of track are you running on? If you tried that in the mid-west in the dead of summer on a rubberized track you would probably burn your feet and get blisters. My younger brother has tried it and experienced as much.
I run around Boston on sidewalks and in the road and it doesn't tear up your feet too bad. The first few times I had a couple of blisters but lately I've been fine.
