BetaCategory: WordPress - Owner: PaulDavis - Owner ID: 1
A basic implementation of WordPress Post Thumbnails
http://markjaquith.wordpress.com/2009/12/23/new-in-wordpress-2-9-post-thumbnail-images/
'true' means that the images are cropped square, the rest should explain its self.
add_theme_support('post-thumbnails', array('post'));
set_post_thumbnail_size(140, 140, true);