Ever since Google Analytics changed their session parameters August 12th I have seen a 20% jump in organic traffic & bounce rates along with a decline in pages/visit and conversion rate. To be clear, I don't put a whole heck of a lot of stock in these metrics as stand-alone indications of how my site is performing.  I'm just trying to get to the bottom of this blip. I noticed some other people mentioned a similar phenomenon in other SEO forums and blog comments, but nobody seems to be talking about this here at SEOMoz (unless I just haven't looked in the right place). I'm not saying the change I noticed has anything to do with the session update, I'm just wondering if anyone else has experienced something similar so that I can either cross it off the list of possible causes or explore further.

At some point in the past I read or was told that No Index, No Follow tags on category and tag pages were a good thing on a standard WordPress blog in order to prevent duplicate content issues. Is this still true or was it ever true?