First things first, this set of rankings is based on data from GitHub and StackOverflow. Read the post for the details on how this data was collected.
There are plenty of other ways to assess the popularity of programming languages, but this seems a reasonable approach.
It’s notable that Swift has tied Objective-C. As the post says:
Finally, the apprentice is now the master. Technically, this isn’t entirely accurate, as Swift merely tied the language it effectively replaced – Objective C – rather than passing it. Still, it’s difficult to view this run as anything but a changing of the guard.
Pass this along to your dev friends.