Thinking back to how they marketed this phone before it was released (namely by NOT marketing it) there may be a correlation with the commercial dropping while the phone is out of stock.
They did an extremely good job of making this phone "viral". They had people all over the internet fighting to learn about their phone without even acknowledging it existed. Now that enough of a portion of the market has their hands on the phone to create a buzz, they are creating a likewise demand by hyping it and having it somewhat unavailable. The elusiveness makes it more appealing, and more people will demand this device.
IF this is what Verizon is doing, it is genius.