I maintain that people who think they are losing privacy are actually just realizing they never had any to begin with. To wit: I tweet my location and now people know I'm not home. Well guess what... There's about 435342636531613 other ways for people to know I'm not home. Like, I dunno, knocking on my door, or calling me at work, or how about just looking at their watch and realizing that, hey, it's 1pm and this dude's probably at work. Duh. Like before twitter came along it was some unfathomable mystery whether someone was home or not.