Well stop it is not exactly the word I want, but I cannot find another one. Basically starting tomorrow Google will track everything you do across everyone Google property you are logged into and share it with anyone they want. Wow, sounds scarey right? Well, actually, they are pretty much doing that now, just not in a clear efficient unified way. Heck, your every move is already being tracked from the cookie level, to what the routers sees to what your ISP sees. And your world has not ended yet unless you practice unsafe web browsing. Then I guess your just asking for it. First off the Google bit. Here is what you can do to reduce the tracking. From Gizmodo..
Now, if you’re paranoid about your activity turn off your history on Google and YouTube, and any other Google service like picasa for which there are instructions here and here. And if you’re really paranoid, you can also consider getting rid of your Google accounts entirely.
BTW, if you do not already practice safe web browser, you may want to give this a read..