The MacRumors forum poster - named Jimpo - says the 16GB iPhone is already in stock at the store where he works and that an announcement is imminent. This could be just the boost the iPhone needs ahead of Christmas - and, of course, its UK launch which takes place on Friday 9 November.
iPhone vs iPod touch
The launch of a 16GB version of the iPhone is eminently sensible. You can already buy the practically identical iPod touch with 16GB on board. It would also help boost the iPhone's desirability in the UK where only the 8GB version is available.
If the Apple Store unveiling is true, it could also herald another price cut for the 8GB iPhone, with the 16GB version taking its place as the high-end model.
Apple has already killed 4GB version of the iPhone that had previously been on sale in the United States.