The Customizer is one of the least known yet most powerful features of WordPress.
We need to get past thinking of it as the “Theme Customizer” which only good for tweaking colors and a limited number of settings.
No, the Customizer provides a framework for live-previewing any change to WordPress.
In WordPress 3.9 I led development of incorporating Widget management to the Customizer, and I’d like to get on a soapbox to get people excited about developing their own custom controls for the Customizer.
Organiser’s Note: This is a Dev/Tech talk that we’re squeezing into the schedule at the last minute. It’ll be fun!