I agree bnhall. "Allegra" seems more like a purging / penalty, than an update. Sites in my theme without adsense, haven't moved at all this month, yet my site went from #1 to nowhere. The site is a clean site, no shady seo practices at all. I keep wondering if adsense opened me up to getting hit by Allegra, perhaps tossed in with all the "made for adsense" sites and directories they're liking trying to purge? Not sure what to think of all this.