It should be a combination of both, but it's not just that. I think a lot of people was gonna switch to ps4, despite the DRM , mainly because the support that ps3 received all these years.
The important thing is, Playstation was and is still the stronger brand. Just take a look at the sales of ps3, releasing a year later (4-5 months more in Europe), complicated structure, and the high price it had.
The first buyers are mostly the fans of every company, the price make a difference, yes, but someone who can paid $400 can add $100 more. The first figures just shows Sony is taking back what they lost in the US for bad decisions with ps3. On the other hand Europe will be Sonyland more than ever.







