JSitemap coupled with Google Webmaster Tools is the sure way of getting your site's content in the Google index as soon as possible.
Sitemaps are the default way of submitting content to search engines. There are several ways of creating sitemaps, however since Joomla contains dynamically changing content, you want your sitemap to be updated constantly to update your current content.
JSitemap allows you to create a dynamic sitemap, always staying current with any changes in your content. It also integrates with 3rd party Joomla extensions to make sure it also creates a sitemap for content coming from other extensions such as K2, forums, directory extensions and any others. Thus instead of waiting for the GoogleBot to index your content, using a sitemap, you are ensuring that all your content is being indexed as soon as the Google crawler accesses your sitemap url.
Therefore, if you still haven't done this, create a Google Webmaster account, verify your website, and submit the url created by JSitemap as a sitemap. This plugin is completely wizard driven so you don't have to worry at all. You'll also be able to submit the sitemap to Bing and Yandex which are good places to get some traffic from too.
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