In Australia yesterday the Financial Review posted an article on developments in this field, lead by a Professor Ben Eggleton at Sydney University and a program called CUDOS.
Apparently this professor has a way of slowing light right down in a way that doesn't degrade the signal in the slighest - a major breakthrough.
Google "Slow light CUDOS and Sydney University Physics" for lotsa links
I think you'll find the underlying method is althought light or electricity carriers move at lightspeed , a signal has a wave front that moves at a slightly slower rate due to collisions, absorption and re-emition of a carrier. For electricity in a non super conductor the signal front can move at 1/10th of lightspeed, even though each individual electron is moving at much higher rates. I guess researchers are trying to produce all digital, optical carriers that can slow light down where they have to (read lotsa collisions) to get a really good signal to noise ratio.