I'm wondering the same thing about Find my iPhone because I'm not updating to 4.2.1 until I know what the unlock situation is like...maybe moving in 6 months and therefore may need to unlock my phone for the first time. Until I know how that will work/on what baseband I don't want to upgrade yet.
Because he/she probably wants to preserve their untethered jailbreak or are waiting to hear what the unlock situation is like. 4.2.1 does nothing to warrant ruining your jailbreak for a tethered one. Find My iPhone is nice but I play with it way too much to lose it and always have it on me.
no, because you need to use the mobileme setup from the mail settings and your itunes ID won't be recognized on 4.1; you need 4.2.1 for the mobileme settings setup for it to have that feature, I'm running it on my 3GS w/ 4.2.1 w/ no problems...
Because he/she probably wants to preserve their untethered jailbreak or are waiting to hear what the unlock situation is like. 4.2.1 does nothing to warrant ruining your jailbreak for a tethered one. Find My iPhone is nice but I play with it way too much to lose it and always have it on me.