iPhone: Upgrading from 3.0 to 4.0.2 I have a quick question regarding upgrading to 3.0 to 4.02. To me this seems like common sense but I just want to double check before moving forward with the upgrade. Will he update wipe everything on my phone and then grab my backup in order to repopulate photos, contacts, sms, phone log, etc?
Yes, it will wipe out everything, install new OS and restore from backup (if you choose to do so). So, make sure you back up before upgrading.