An Apple spokesperson has indicated that a future software update will address an issue where the Apple iPhone battery icon may not show a full battery despite the fact that the battery is fully charged. A survey on WirelessInfo suggests that as many as 60 percent of iPhones could be affected. Some further testing by WirelessInfo also found that the affected batteries may simply require some conditioning before they can hold a full charge. After an intense series of charging/discharging sessions, the problem batteries on our test iPhones seem to be lasting for longer periods, so this may have been an issue with the batteries requiring some conditioning.
Apple has not posted published any further details and has not disclosed when the update would be available.