I love that the replies are full of people who, like me, don't mind if advertisers know more about me. Why wouldn't I want to experience more relevant information about purchase opportunities? What's the alternative? Random stuff that doesn't apply to me? Sites who can't bring in enough revenue to operate that I don't get to use because they can't target me specifically?

I'm confident in my ability to say 'no' to an advertiser, just as I appreciate being told about things that might help my lifestyle. I'll research it, I'll look at the pros and cons as well as the costs and will make the final decision.

Although, fair disclosure, I run an ad blocker in my browser, so I don't see most of the ads anyway ;)

PleaseRobMe was a fun little project that those with a heightened concern for privacy love to point to, but I doubt it ever led to anyone having their house robbed. Again, the benefits of me being able to selectively tweet a conference hashtag and see if anyone wants to hang out in person outweighs the fear that someone's going to see if I left any Apple gadgets at home to steal.