I find it very necessary to make sure that I have installed the Google (XML) Sitemaps Generator for Wordpress plugin on all my wordpress installations. It makes creating a site map extremely easy and is a one step process. The best part about the plugin is that it does not require any PHP coding what so ever so even the unexperienced blogger can create their sitemaps.

Sitemaps are sometimes underrated because many forget to put one up. I suggest that each of your sites maintain a good functioning sitemap that allows the main crawlers (Google, Yahoo, MSN) to crawl your site ALREADY knowing where to find the pages.

Many Black Hat (and White Hat) web marketings/programmers like me make sure that a good functioning sitemap is ready for the bots to crawl. Do yourself a favor and download this plugin for Wordpress 2.1 and above (which you should have upgraded to by the way).