Browsers can load page elements in parallel. Specifying different domains for media, skin, and JavaScript URLs in the Magento Enterprise Edition configuration (System † Configuration † GENERAL † Web) will help speed the page rendering time in the browser, as most browsers limit the number of downloads to 2-4 parallel threads per domain name.
Other web page design recommendations are beyond the scope of this document. You can find the detailed list of web site design best practices at the Yahoo Developer Network at http://ping.fm/AXhAv
