The Kansai Electric company in Japan has deployed new equipment that enables them to transmit 1 terabit of data per second over their company fiber lines.
That is 100 times faster than most of the fiber transmission electronics currently in use, and shows why fiber, while somewhat more expensive on the front end, is such a safe bet. Research in laboratories has actually achieved even higher speeds, but the Kansai equipment has actually been deployed in the field. Fiber can be upgraded without replacing the fiber and duct lines in the ground or on poles, which is a big advantage, and it makes fiber future proof.