http://www.zoom-in.com/blog/2007/03/first_impressions_top_5_stando.php
From the site:
My current favorite five new PsCS3 features in order are:
1. Nondestructive Smart Filters
2. Quick Selection Tool & Refine Edge
3. Photomerge with advanced alignment and blending
4. Automatic layer alignment and blending
5. Vanishing Point with adjustable angle