First, the summary: These guys have figured out a way to build a map of the surface features of Earth-sized planets at least as far away as Proxima Centauri. Let that sink in for a moment. Just 30 years ago, nobody could even detect exoplanets at all! And even at the beginning of this year, we were still limited to finding planets that "shook" their parent star by a fairly significant amount (so, either big planets, or really close).
Now, for anyone with the stomach for actual science rather than that (somewhat sensationalised) summary, here's the video (about an hour):