WordPress Moving Forward
One of the biggest complaints about WordPress’ commitment to backward compatibility is that it’s hard to move forward when supporting old versions of PHP.
Recently (I became aware today) the requirements for WordPress have been updated to be php 5.6+ instead of 5.2.4+, which means some deprecated code can be dropped and new ways of doing things can be implemented much easier.
This is great news for anyone not running a version of PHP < 5.6, but ideally that should be most people running WordPress.