This could be a long shot!
My website (geographyalltheway.com) seems to have dropped out of several keyword searches for Google. The site is still indexed (with a page rank of 5) but where it used to rank very highly for searches for things like 'ib geography', 'igcse geography' and 'geographyalltheway' it doesn't anymore.
Could this be due to the sitemap? I have the standalone sitempa generator working through a cron job to produce a weekly sitemap. Could this be a cause of my problems? I'm getting rather stuck for ideas?