I have a large forum and it has been getting more and more pages indexed due to the sitemaps, however in recent days it seems to be dropping fast! The problem seems to be that its not readying all of the sitemaps from the sitemap_index.xml.gz file. When I look in GWT it only shows sitemap sitemap_2.xml.gz sitemap_4.xml.gz and sitemap_6.xml.gz. Very strange as it reports no errors or problems.. Anyone else experiencing this?
What kind of plugin do you use? SOme plugin need to be restarted once in a period to be functioning again.
I use vbseo's sitemap for vbulletin which is running on a cron.. I use google webmaster tools (GWT).. It's very strange because traffic has not slowed down.. to me it looks like a problem with google reporting the details incorrectly..
what's your url? and are you using the Latest version of the vbseo sitemap? it shouldn't be that hard to fix pm me if you are not able to figure it out, I'll try to give you a hand