Since then a lot has happened. Shortly after this, the Linux kernel repository was compromised, leading to re-validation of user credentials. This led to a few discussions on the kernel.org platforms security, and the use of SHA-1 checksums for file validation within the Git infrastructure that hosts the Linux kernel development code bases.
Since then we’ve moved from the version 3.0 kernel, released on 21 July 2011, through to version 4.0, released on 12 April 2015. Version 4.7 was released just recently on 25 July 2016. In total 27 versions have been released approximately every 70 days since then. (The dates have come from the kernelnewbies wiki.)
There have been many changes to the code since then, primarily the largest additions being new drivers to support additional chipsets in the graphics, networking storage driver and CPU categories. In addition, some new features and capabilities added to keep Linux at the forefront of supporting new platforms. Given the level of development investment, I’d imagine Linux to be around for several more years to come. And if not, then it’s open-source philosophy will contribute many ideas to future systems.