To all unibody MBP owners: Can you take a quick look in your USB / FireWire / Ethernet / MDP ports and especially inside your ExpressCard slot if you're using it? Please let me know if there are any dark grey / black spots or marks in the ports. My friend and me both got these spots after 2 weeks of over-protective usage. Does anyone know the cause of this? Maybe a reaction of the electrical current that goes through the ports with the anodized aluminum?