Both the Incredible and Supersonic have had their leaky moments, and due to the similarities it's difficult to tell which model is shown here. I'm leaning towards the Incredible, which is meant to be the Verizon version of the Desire.
The video's in pretty poor quality, but you can see it's got the same ridged back as previous photos have shown - and while the back is red, I wouldn't read too much into that, as HTC always does coloured parts for prototypes, favouring pretty basic colours for the launch. It's definitely a US-only device, shown running Verizon Wireless - but also lacks the chin that European Android phones from HTC always have.
When I had a briefing with HTC about the Legend and Desire, they told me every Android phone destined for the European market will have a chin, with US launches lacking one.
Check out the video for a shakycam look at the Incredible (or Supersonic), and let me know what you think. There seems to be a deeper bezel on the bottom half, like the Incredible - is that where the optical trackpad is? It's a bit hard to make out. [Phandroid]