google deindexing my pages

Over the past 2 weeks, google has been deindexing my pages everyday.
site:mysite.com
i had 8k+ last week .. and now its 6k .. :|
Its an autoblog with wprobot, with auto tagging...
most of the pages are tags, so google just deindexing my spammy tag pages?

Sounds like a reasonable explanation. As long as you main content pages are not having a problem I would not really worry.

Is there a lot of DC on your site?