Grooves in rotor
 

I was just balancing the pressure in my tires when I noticed that my front-left disc had grooves in it, while the other three were completely flat. Is this normal, or is there a problem with the pad?

Here are the grooves:
http://www.cim.mcgill.ca/~ericb/photos/disc-small.jpg

A higher resolution image can be found here

Any insignt, or confimation of my paranoia would be appreciated.

Cheers,

Eric

This belongs in the maintenance area, not performance.