Google Site Maps
The latest version of our content management system (CMS) will automatically update a special Google site map file every time you add / update /delete a page.
Google site maps have been developed by the company to allow web site owners to tell them the frequency that the pages in a site are updated. This helps Google as they don't want to waste computer time spidering pages that haven't changed since 1995. Once you have set up a Google site map you can get a lot of information from Google on how frequently the site has been spidered, which terms it is appearing under etc. It doesn't seem to do any harm at all to your search engine positioning either.
A major benefit is that you can tell Google where every single page is on a web site. This is of great benefit for online shops that have hundreds of products as often these are generated with long query strings: ie (http:/www.myshop.com ?productcode=1998 &category=underwear &prodtype=underpants) sometimes it is difficult to for search engines to reach pages like this as they are often changing, with a site map this problem goes away.
Once set up, you do not have to worry about it. As each time you edit a page, the site map is updated and Google will notice the difference and and re-spider accordingly.