Sitemaps are particularly beneficial
on websites where:

• Some areas of the website are not available through the browsable
  interface,or
• Webmasters use rich Ajax,Silverlight,or Flash content that is
  not normally processed by search
  engines.

从Wikipedia – Sitemaps开始

请记住：

Because most web crawlers do not
execute JavaScript code,publicly
indexable web applications should
provide an alternative means of
accessing the content that would
normally be retrieved with Ajax,to
allow search engines to index it.

从Wikipedia – AJAX Drawbacks

此外,您可能有兴趣查看以下文章：

> Official Google Webmaster Central Blog – A proposal for making AJAX crawlable
> SoftwareDeveloper.com – How to: Get Google and AJAX to Play Nice
> Crawling Ajax-driven Web 2.0 Applications