Does Everything I Want
I have my phone, my wifes phone, and my daughters phone registered under one account. I have linked them all to Googles Latitude web interface (the iPhone App causes too much battery drain) and set the update rates to "tower switch + 1 hour".
I then access my Latitude web page to conveniently see all three locations. Updating our Google profiles with pictures makes the position icons show our portraits; very slick interface. My wife and I can track each others location, as well as our daughters location whenever we want. Tracked my wifes & daughters location as they made a series of connections on an overseas flight. I highly recommend this app.
RonMcF about
Device Locator, v1.0.1