The WordPress SEO premium plugin adds several features to the WordPress SEO plugin. At the moment, the extra included functionality includes:
A redirect manager
This allows you to create and manage redirects from within your WordPress install, allowing you to easily redirect old URLs to new ones, and solve common issues. This is especially powerful because of the combination with the Google Webmaster Tools integration.
Integration with Google Webmaster Tools
The integration with Google Webmaster Tools in WordPress SEO premium allows you to retrieve crawl errors from Google Webmaster Tools and fix them immediately using the redirect manager.