ThemeSorter (http://www.themesorter.com) is a new website that makes it easy to find premium WordPress themes from different sellers. You can search by any combination of category, color, features, rating and price. This is made possible by the indexing of themes from various sellers. Screenshots and theme details are provided with links to live demos, user comments/ratings and other helpful information.
We have 220 themes at launch this week and are on schedule to increase that to 1000+ this summer.