I just saw something really bizarre in my raw logs.
Google, according to the log, brought a visitor to Site A that usually comes from Site B. Site B has top 10 ranking for the search phrase; whereas Site A has none of the keywords, and never brought any visitors before for those keywords.
Both sites are on the same server. Either the raw logs got their wires crossed (which I have never seen before, and I've looked at the raw logs for different sites on the hosting account many times in the past). Or Google got its wires crossed.
I can't figure out another explanation.
If the latter situation is indeed the case, it would indicate Google's algo somehow looks at various websites on the same server and this glitch exposed it.
(The visitor came via EARTHLINK, INC in NYC. The timing, if anybody else happens to see the same anomaly, was 08/Nov/2008:21:49:35 -0500.)
I've made a mistake in the past with putting Google Analytics code for one site into another. But here's we're talking about raw logs.
"GET / HTTP/1.1" 400 312 "http://www.google.com/search?hl=en&q=keyword1+ keyword2&aq=1&oq= keyword1+keyword3" "-"
Note: There weren't any 301 redirects or any other redirects involved in this (at least not at my end). Google, however, may have done some funky redirect, e.g: default to a secondary site on the same server, based on some matching data in its historical site profile (connecting one site to another).