Is there any new information gained from the optical observations in this particular instance? Did the initial gravitational wave detection allow us to capture the optical counterpart at an earlier stage than normal and therefore get more information as a result?
Yes, absolutely. This wasn't a very large gamma ray burst - as far as I know it may have not been followed up at all. GRBs are hard to localize - but the detection of the gravitational wave made it possible to search for the source quickly in a much smaller area of the sky. This got a lot of people looking, and a lot of good data collected.