SXSW 2012 may be the year of ambient awareness apps. At least, there's an awful lot being written about them. These are the apps that tell you about friends or "relevant strangers" who are wandering around near you. Among the companies showing of their apps will be Sonar, Highlight, Ban.jo and Trover. With so many people and so many events flowing around downtown, SXSW is a great place for these things to duke it out. (David Spark aptly calls SXSW "fluid.") It'll be interesting to see how many "relevant strangers" I find as I try to find the hottest party. The hottest taco truck. The hottest mechanical bull...