It's a perfectly legitimate question in light of the available sales numbers.
As most are well aware, Sony announced that the PlayStation 4 had sold over 2.1 million units worldwide, making it the biggest launch in the brand's history. Soon after, Microsoft revealed that the Xbox One had sold over 2 million units as well.
When the November NPD results arrived, it was apparent that while the PS4 had sold more during the month, the Xbox One technically sold faster. There are other factors to consider, including availability and the fact that the PS4 was out a week earlier, but the bottom line is that the numbers – for both the US and worldwide – are awfully close. It's exactly what I predicted heading into the launch; I never believed PS4 would outsell the Xbox One in the US but if it was close, that'd a a big-time coup for Sony.
We're coming off a period of seven or eight years where the Xbox 360 continually outsold the PS3 by a 2:1 and sometimes 3:1 ratio here in North America. To have the Xbox One only manage to sell as many units as the PS4…? Is it not fair to assume that at least some former Xbox followers switched sides for this generation? Granted, many avid gamers will eventually want to own both consoles, so maybe some just sided with the PS4 first. They'll grab the Xbox One later (maybe after a price drop). Even so, there are a great many gamers who say they're good with one system.
And if that one system is the PS4, and you were once a die-hard Xbox supporter, what happened? We could probably come up with a few ideas, right? I'm just wondering how many supporters Microsoft lost during the course of 2013… It appears to be significant.