customize_preview_init

/**
 * This outputs the javascript needed to automate the live settings preview.
 * Also keep in mind that this function isn't necessary unless your settings 
 * are using 'transport'=>'postMessage' instead of the default 'transport'
 * => 'refresh'
 * 
 * Used by hook: 'customize_preview_init'
 */
public static function mytheme_customizer_live_preview()
{
	gc_enqueue_script( 
		  'mytheme-themecustomizer',			//Give the script an ID
		  get_template_directory_uri().'/assets/js/theme-customizer.js',//Point to file
		  array( 'jquery','customize-preview' ),	//Define dependencies
		  '',						//Define a version (optional) 
		  true						//Put script in footer?
	);
}
add_action( 'customize_preview_init', 'mytheme_customizer_live_preview' );

/**
 * This file adds some LIVE to the Theme Customizer live preview. To leverage
 * this, set your custom settings to 'postMessage' and then add your handling
 * here. Your javascript should grab settings from customizer controls, and 
 * then make any necessary changes to the page using jQuery.
 */
( function( $ ) {

	// Update the site title in real time...
	gc.customize( 'blogname', function( value ) {
		value.bind( function( newval ) {
			$( '#site-title a' ).html( newval );
		} );
	} );
	
	//Update the site description in real time...
	gc.customize( 'blogdescription', function( value ) {
		value.bind( function( newval ) {
			$( '.site-description' ).html( newval );
		} );
	} );

	//Update site title color in real time...
	gc.customize( 'header_textcolor', function( value ) {
		value.bind( function( newval ) {
			$('#site-title a').css('color', newval );
		} );
	} );

	//Update site background color...
	gc.customize( 'background_color', function( value ) {
		value.bind( function( newval ) {
			$('body').css('background-color', newval );
		} );
	} );
	
	//Update site title color in real time...
	gc.customize( 'mytheme_options[link_textcolor]', function( value ) {
		value.bind( function( newval ) {
			$('a').css('color', newval );
		} );
	} );
	
} )( jQuery );