I'm not worried about being tracked. I don't do anything to worry about on the Internet. If tracking and surveillance stops bad things from happening or brings criminals to justice then long may it continue.
I agree with this. A large amount of the data we "share" online is pretty innocuous - most people aren't going to be all that interested in my collection of wedding snaps, for example. But that's not to say that there isn't some very scary stuff we put online quite freely - frankly I'd be more concerned about financial information we share with companies without a moments hesitation, and we all remember
this particular state of affairs I'm sure. If you are at all interested in data security, have a read of the books by Kevin Mitnick - they are very enlightening.
But to anyone who is concerned about the Google situation head
here. Have a look at the data Google is using to sell you stuff - if you don't like it clear it out (and otherwise snigger at how inaccurate it is). Similarly, if you are a regular Google user, and have a Google account, head
here and do likewise.
And for what its worth, and without wanting to come across as too much of a Google fanboy, bear in mind that some other companies don't make it quite so easy to clear out your data.