If you watch an old tech talk re: Google disaster recovery topic, the Googler explains that a user's info is never fully deleted because it's too expensive to do so given back-up duplication is processed multiple times in multiple locations and sometimes over multiple technologies. In other words, cancel your google account today and your data may be "deleted" but it's really, as in actually really, still on magnetic back-up in several locations, but it's just really hard to get to and put back together, so is considered "gone". Unless you're a really big organization with the means to go to such troubles, like maybe the government or Google.