He made it pretty clear in the op that he was talking solely about day 1. And again u are talking about launch window.
No, he didn't. He said launch. That's it. Launch is the release of a product and almost never refers to one day. Ford is launching a new Mustang for 2015. When we look back and discuss if it was a successful "launch", we will look at everything associated with launching it. The reveal of the car in December at various locations around the world. The on-sale date later this year. Advertizing. Early sales of the car, etc. Almost no one will discuss day 1 sales of the product.
I am talking about the launch of the product which is a video game system. In doing so, as most everyone does, I would reflect on pre-release hype, sales, the system, the games, the reception, launch window games, etc.
If you are talking "launch day", that is something specific. Just as "launch Window" is. I am discussing the overall "launch", as most people in this thread did, since that's what the term means.
Note that in the description below talking about the biggest launches, the article mentions 24 hr sales, 48 hr sales, 2-week sales, and even references shortages last months or years. We look at much more than 1 day when evaluating a system launch.