Well, as much as going light-speed would revolutionize space travel, its not "fast enough".

For reference, the closest galaxy is 25,000 light years away, which would take 25,000 years to go to (or come to us) at the speed of light. Assuming of course theres no one except us in the Milky Way, and that there is someone in that galaxy. If someone is even "only" 1 light year away, it would take 1 year to send/recieve a message. Unless they send a spaceship to directly communicate with us that is.