It likely will not be the last.
The Detroit News: British Airways jet may have been hit by drone
Drones will likely become more and ore of a problem in aviation. It's not just the average clueless hobbyist that may inadvertently violate controlled airspace and smack a plane by accident while flying their drone around obliviously. People intent on creating harm - terrorists, criminal extortionists, even vengeful spouses may soon be able to target a drone at a passenger plane and cause serious damage and destruction.
Given the rather radical population in easy drone flying distance of Heathrow's approaches, it is too early to tell if it was simply stupidity or active malice that led to the collision. Luckily no harm seems to have been done, this time.
There are no good nor easy answers for it, as the technology is well and truly already out there for good (of which there are many good and decent uses for drones) or ill.