Last month, rumors emerged that Facebook may have been buying Hot Potato. As Doug Caverly described , "Hot Potato is a check-in service that takes possibilities other than physical locations into account. Users can, for example, say they're listening to a particular song or reading a certain novel, not just check in at a concert or a bookstore." Hot Potato posted to its blog today that it has indeed been acquired by Facebook. "This wasn't an easy decision,