The GameStop chart is the only truly relevant one, IMO, because of how much skin ($100!) you need to get in the game.
The other lists, however, tell an interesting story. You have the PS4, a bunch of PS4 software, and just the Xbone hardware.
Who buys just the console hardware without games? Optimistic, stupid scalpers is who; they fail to realize that a $500 box with terrible buzz is not going to fly off shelves this fall.
For the record, I don't think it will be terribly hard to find either console at retail this fall, but anyone getting excited about the Xbone's future based on an Amazon chart needs to look at the entire chart for the full story.
Tin foil hat extra credit: Why are there still Day One Xbones available, even though initial allocations were shut down shortly after the unveil? Two options: Microsoft gave retail more allocation - a LOT more allocation, like a heinously huge amount. Or, and everyone adjust your shiny hats, they had massive amounts of cancellations, releasing tons of stock back into the pool. Based on the fact that the Amazon PS4 bundles are hugely popular, and didn't come out until several days after what I'm sure Microsoft has internally termed "Xboned Monday", leads me to believe the cancelers snapped up a different box.