For primary keyword combo, my 9-year old site is not showing in one index version I'm seeing from a few of my computers, while my wife's computer sees a different result with my site at the bottom of page 1. I've seen a drop in traffic, registrations and orders since the 17th.
I don't really push SEO anymore. Basically I just let my site and the content do the work. I hope not to be penalized for having "old" content... there's only so much you can say about the subject I target and regurgitating content sucks.