Sorry for being slow to get back to you.
I was unaware of that file until you mentioned it. (It's much easier to read in TextWrangler than in Terminal.)
My file
did not list any of the tracking garbage that ryck's listed, possibly because I'm running Ghostery?
My file
did list an incomplete compilation of my recent Google searches (none of which were "Advanced" searches), but it also listed a coupl'a searches of my PayPal history and a coupl'a other searches that were done
without Google involvement, which suggests that Google has nothing to do with it.
My file disappeared when I cleared Safari's history and hasn't reappeared after a coupl'a Google searches (including one that was originally listed).
I dunno.
Edit: Add
link to screenshot.
Edit 2: Interesting sidenote... If I clear Safari's history via Safari > History > Clear History, /Users/artie/Library/Caches/Metadata/Safari/History is cleared of
all files, but if I clear it with Cookie (3rd party d/l),
all files remain, although Safari > History shows nothing.