ZDNet: Tech Update: Networking / 10G Ethernet arrives
Unless you work for a telecommunications carrier, it isn't likely that you'll be buying 10G gear anytime soon. It's not LAN equipment for the vast majority of networks today, given the volume of traffic that typical business LANs carry. It's also not cheap: expect to pay $40,000 to $100,000 per port if you plan to become an early adopter. If the price curve follows the past examples of Fast and Gigabit Ethernet, costs won't come down to reasonable price/performance realms for three or four years. At that point, the largest of enterprises may be able to turn to 10G for high-volume backbone switches.

Carriers, however, will be installing 10G routers, and that opens up some interesting possibilities for their customers. If you have two geographically dispersed locations, you could connect them across a single metropolitan area network (MAN). Such a topology will be faster, simpler, and possibly even cheaper than employing frame relay, T-1, or other older wide-area networks.
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