As with most physics experiments for the last 40 years, nothing new was discovered that we didn’t already predict. Confirming something widely believed to be true isn't nearly as valuable as finding out we don't understand something. This is actually one of the reasons I dropped out of my physics phd program.
Because this is astrophysics and not particle physics, this discovery is just the beginning! We don't know the rates of these mergers, the distribution of the masses of the binary components, what electromagnetic signature accompanies the events (if any)...
We've known gravity waves existed since the Hulse-Taylor pulsar, so just observing them for the first time is not nearly as interesting as the science to come in the next decade. Advanced LIGO is a powerful new tool that will open up exciting new observations.
