Now that the new iphone has a magnetometer to go along with the GPS chip, one thing I haven't seen anyone mention yet are the app possibilities for hikers. Turn-by-turn navigation is now available from AT&T (and TomTom is coming), but that only uses the GPS chip; with the compass feature, there are tremendous possibilities for navigation uses off the beaten path. Plus out in the woods you don't need cell service, as the GPS and magnetometer will work wherever you are. My phone is always with me, and I've always wanted to eventually buy a handheld GPS...it'll be nice to combine it into one very slim, very lightweight device. Hopefully TomTom/Magellan/Garmin etc. are actively working on this for us backpackers.