A feature plugin for core to provide Two-Factor Authentication.
In order to better combat brute force login attempts and stolen passwords, WordPress needs a standardized-yet-extensible core system for providing opt-in Two-Factor Authentication to users. This, hopefully, is that system.
We are aiming to be ready to merge in to Core in February of 2016, during the 4.5 release cycle.
For more history, see: http://stephanis.info/2013/08/14/two-cents-on-two-factor/
