Google Analytics is simply used for site owners to check statistics. I don't know if Google uses or even has access to this data, but it's a great tool (I use it)
That is all it does in case anyone is worried, it is an analytic tool for site owners to analyze traffic coming to their site, nothing else. I use it on my sites also.
I dunno, Google comes across as a "you scratch my back and I'll scratch yours" kind of company, so I find it hard to believe that they're providing site owners with google analytics free of charge and not making some use of it themselves. What made me suspicious is when I was on Yahoo7 here in Oz to check the news, weather and TV guide... every page change/refresh and google analytics was there. Hmmm, just seems strange that Yahoo would use its main competitor to monitor site traffic???
Oh, and this is for those who will say other companies do this kind of sneaky underhanded thing as well (mainly Kona
).... I know other companies are out there tracking internet users to see how they can make use of them. For example, on Yahoo I notice 'Doubleclick', 'RightMedia' and 'Yahoo Overture' are there at every page change, and I believe these trackers are designed specifically to extract information purely for advertising purposes.
Is this for Firefox users only?
As far as I know, yes. 
it is an analytic tool for site owners to analyze traffic coming to their site
I find myself wondering - what does it tell you? Seriously, I'm curious.
Yeah, but I'm more curious as to what it tells Google??? I mean, they can identify your location and IP address, so why wouldn't they use your interests and surfing habits to target you with specific ads... particularly with clients ads local to you?? It is their primary business (advertising), and it's what they do, so I'd believe in the existence snowballs in Hell before I believed Google would pass up on an opportunity to advertise/sell.
If there's anything I dislike... er, hate more than bankers and politicians, it's effing advertisers. The bastards ply their trade in every free space and location imaginable... and it is so unsightly 99.9999% of the time, with billboards and advertising placards desecrating the scenery.
So yeah, look out if you happen to be chucking a brown-eye (mooning) at the referee for a bad decision during the game.... expose it for too long and they'll slap an ad on yer arse.
