Elfchen - 5:15 pm on Feb 16, 2011 (gmt 0)
When you add google code to your website - no matter if analytics or adsense you allow google exactly to monitor all your traffic. This will allow to recheck your status and rank in detail. If you have tricked in the past they can easy detected and remove you from the index. But ... after 6 years normally your sites will come back if it is deindexed (no joke - that was the waiting time for my domains).