Light Peak isn't really a port standard like USB or Firewire, it's a consolidator. You can run USB over Light Peak, same with Firewire, HDMI, Audio, Networking, etc. The goal with Light Peak is to connect two cords to your laptop (power and Light Peak) and have everything connected to the other end of Light Peak (Monitor, USB keyboard/mouse, Firewire drive, Ethernet, etc), making it much less cluttered around your laptop and enabling you to pick it up and go fairly quickly. This really shows off in smaller devices, take a Netbook or a Tablet, instead of needing all that space and hardware for USB, and the like you can simply route it over Light Peak and have one connector take care of it all.
Since this is an Intel standard (albeit sponsored and pushed by Apple) it doesn't come with the restrictions that Apple would have placed on it if it were their own standard. This should be fairly open and available. I bet within a year, two at most, nearly all laptops will have this port, and there will be expansion cards available for PC's to add the port. That is, unless it's a total flop, which is possible.