Ooh boy, do we have a good one for you today. We've been tipped off that the HD3 -- HTC's mythical successor to the wildly popular HD2 -- is not only alive and kicking, but headed for a bright and sunny Windows Phone 7 future, starting as early as October 18. Before we get too far ahead of ourselves, all the evidence we have for now is the above spreadsheet, which we're told is an internal planning doc from UK carrier O2. It's not exactly the hardest thing in the world to forge so keep your skeptical wits about you, but as silly as this inflationary renaming to HD7 may sound, we find it strangely believable. After all, why wouldn't the company that brought us the Incredible Wildfire of Desire jump ahead a few numbers to keep up with the hot new OS' numbering?