What complications will arise from personal on-line data storage in the near future?

It seems like more and more personal data can be kept online and viewed by others these days. Sites like Boxedup and Google Books can keep track of items you own. Don’t you think someday burglars could easily look up what personal items you have and say, “Hey, this guy’s got the complete Harry Potter book set… let’s get it!” It seems like it may come to the point where you can place everything you own, all your personality traits, people you know… everything about you on the internet. Will it go too far? How much information will you give away (knowingly and unknowingly)? Could this be the end of privacy as we know it?