HuskyPup - 8:39 pm on Jun 8, 2011 (gmt 0)
I believe Matt said that if you made changes to your site, then they would be noticed the next time your site was crawled by googlebot and the index changes would take place as they normally do.
I can definitely confirm that I have seen improvements after tweaking a site, not changed it, simply SEO'd even tighter. I have not done this on any of my big sites but one of my niche-targetted .co.uk's and will test similar tweaks on one of my .asia sites soon.
Doing the same to my main B&M .com site is a huge task therefore I need to know I'm right before considering that!