SnowMan68 - 5:15 pm on Apr 12, 2012 (gmt 0)

"We encourage you to make changes to your site so that it meets our quality guidelines. Once you've made these changes, please submit your site for reconsideration in Google's search results. " This would imply that the penalty has already been assessed.

Agreed. That's probably why some people continue rolling on without future drops. And if they get hit 3, 4, 5 weeks later it could be one of the many algo updates affecting their sites.