Robert_Charlton - 10:08 pm on Nov 3, 2012 (gmt 0)

I'm going to note here a new discussion that seems to be more on topic than most of this one, and also to quote from it two posts that Shaddows made which relate to this topic as a whole....

Overnight change in keywords that bring G traffic - but same amount of it
http://www.webmasterworld.com/google/4514405.htm [webmasterworld.com]

From 1script's opening Oct 31, 2012 post...

...I loaded my stats for today and I can see NONE of those top keywords bring any traffic. Judging by the unchanged amount of Google traffic, they have all been replaced by larger amount of different long tails....

And two Nov 2 posts by Shaddows...

We also enjoy long periods of stable referral patterns. We find that a significant referral shift is followed a week or so later by a general re-ranking for our site, which is not part of a main algo update. The reason for this seems to be a re-profiling of the site- at the whole site level. In the past, we have seen completely different customer behaviours either side of a shift. Having been through the process on many occassions (and always one in late Sept to early October), we have contingencies to cater for most valid user-intents, but it usually turns out for the better, eventually.

No, we get a temporary shift, then normal traffic (plus zombies- note this is extra traffic, not replacement traffic) then a completely new referral pattern. Previously unloved (but no less worthy) pages get traffic and increased sales, while solid sellers suddenly stop selling completely. On one scary occasion, a number of our top selling lines dropped 10-15%, but close analysis showed revenue was mostly made up elsewhere. Over time, sales on the top lines returned, but we also kept the new revenue as well. As I said, it can be disruptive but has usually worked out well in the end.