According to discussions on Apple’s support site and several reader reports, it appears iPhone Software 1.0.1 includes a few new features, along with the known bug fixes and security patches.
There is now a BCC: option in the phone’s Mail Settings to send yourself a copy — this was previously only a CC: option.
Passcode Lock timing options have been expanded up to “After 1 Hour,” and it has also been reported that the 1.0.1 update fixes a previously reported battery issue in which the iPhone’s display would not indicate a full charge.