An Idea for a WordPress Post class

WPPost.php

<?php

/**
 * This is a take on making the Post object in WordPress a little more object-y. As well as wrapping
 * some basic function like get_the_title(), it aims to treat references such as "post_parent"
 * as full objects rather than IDs, making it possible to do $post->get_parent()->get_content().
 *
 * No caching has been added, but this would be trivial. Half written in pseudo-code and untested
 * 
 */
class Post {
	
	var _id;
	var _post;
	
	function __construct( $post_id ) {
		$this->_id = $post_id;
	}
	
	function get_id() {
		return $this->_id;
	}
	
	function get_permalink() {
		return get_permalink( $this->get_id() ); 
	}
	
	function get_title() {
		return get_the_title( $this->get_id() );
	}
	
	function get_content() {
		return get_the_content( $this->get_id() );
	}
	
	function get_parent() {
		
		if( !$this->_post )
			$this->_load_post();
			
		return new Post( $this->_post->ID );
	}
	
	function get_excerpt( $length = 55 ) {
		
		// Crap WP excerpt crap
	}
	
	function get_terms( $taxonomy ) {
		return wp_get_object_terms( $taxonomy );
	}
	
	function get_meta( $key, $single = false ) {
		return get_post_meta( $this->get_id(), $key, $single );
	}
	
	function get_author() {

		if( !$this->_post )
			$this->_load_post();
		
		return get_userdata( $this->_post->post_author );			
	}
	
	function get_featured_image( $size ) {
		return get_the_post_thumbnail( $this->_id, $size );
	}
	
	function get_comments( $args = array() ) {
		$args = wp_parse_args( $args );
		
		$args['post_id'] = $this->get_id();
		
		return get_comments( $args );
	}
	
	function _load_post() {
		$this->_post = get_post( $this->_id );
	}

}