Now, I'm no physicist, but here's how I understood what happened. Some scientists built two really long and fancy tunnels with lasers measuring how the long the tunnels were. Really far away, two black holes 30 times the size of the sun smashed into each other. They created a massive wave of gravity that traveled to little old earth. When the wave hit us, the tunnel compressed by 1/1000 of a proton. Which doesn't sound like a lot, but compress it did. So the implications are that Einstein was right, gravity can affect space and time, and Interstellar had some reasonable science behind it.
To be honest, the real scientific implications of this discovery are beyond my meager introductory physics scope. My interest in this subject is on a more basic level, pure amazement at the universe and discovery of it. 100 years ago a man predicted that gravity could bend space and time, scientists were smart enough to build a tunnel to measure this, I'm able to think about a dimension beyond the one I walk around in, and a colossal collision from too far to comprehend squished my world by a tiny amount. Every discovery, every action, every wave makes an impact. How amazing and beautiful is that.