i had to go for the irony of this.
http://www.youtube.com/watch?v=-M05IEIetV82600 hope conference. speaker Steve Rambam. "Privacy is dead, get over it"
Have to say first time i watched it a few years back i learned a lot, but he does talk about a lot of things, some that brushes this. Anyway As near as i can tell the other thing no one has really mentioned on this kind of thing is WHAT is done with the databases. That is that they are sold. Not only does google sell this information, it BUYS it too. meaning even if your using other sites to view your streaming media, their is a good chance someone is going to buy that data. The only real way to get around this (aside from all the add ons) is to either live in a cave or acting like a paranoid luni. by that i mean using every single protection possible(add-ons, proxies, etc) at all times even for something as simple as a search at startpage. Otherwise information about you is being stored, and even then SOME is still being stored by your ISP(such as you got to X proxy first). At the end of the day data is so cheap now that it costs effectively nothing to store everything about you, forever.
because of this i tend to look at it more along these lines: Do i want to hide this information? maybe its a search that could be misconstrued, a book that you KNOW is being watched, or ofc actual illegal activities. If one or more of those criteria are met, then sure to me go all bat shit crazy and enable everything you can, and do all that you can to protect yourself.
Otherwise go with a "stand down" approach, leave on what you want(this will obviously vary person to person, and pc to pc/connection to connection for speed purposes). Personally this machine is so god damn awful i run nothing more than ABP, was forced into chrome away from FF(the memory leak causes the browser to crash about every hour. grrr).
At the same time my normal habits are severely restricted on this machine, the worst that could be found on me is that i come to sites like this, which doesnt bother me. The irony here is that i KNOW im on a watch list. anyone with my prior clearance/job is. however because of that job, its something i would/should normally be interested in, so i dont give a damn if in some file somewhere on some hard-drive in some bunker their is a record i visit sites like this. Anyway i dont know if im even on topic any more so i guess ill go bother someone elses thread.