If you still do not believe that Windows Phone 7 is coming soon to a store near you, there is already another evidence doing rounds on YouTube. A video of LG E900 sporting Windows Phone 7 (WP 7) has leaked on YouTube.
The quality of the video is poor and out of focus but clear enough to show you a six minute walk-through of WP 7 interface and device itself. While much details cannot be gathered from the video besides a side mounted USB port and some form of DLNA integration. From this video LG E900 looks like a cousin of LG C900 minus the keyboard.
Video of LG E900 Running on Windows Phone 7: