They just sent a few test satellites up that use lasers for communications. It's actually superior to any ground based fiber optics.
The single biggest draw of laser interlinks is arguably the major reduction in connection latency (ping) they can enable compared to a similar network without it. By moving a great deal of the work of networking into orbit, the data transported on an interlinked satellite network would theoretically require much less routing to reach an end-user, physically shortening the distance that data has to travel. The speed of light (300,000 kilometers per second) may be immense but even on the small scale of the planet Earth, with the added inefficiencies inherent in even the best fiber optic cables, routing data to and from opposite ends of the planet can still be slowed down by high latency.