During the last three months, it sold combined 404k units in the US, so there's one metric that is not "very well".
The last three months represent the lowest ebb in monthly sales each year, so are atypical what a console on average a month year on year. If you total the PS4 units, while better than XBO, they still don't reflect the US contribution to 10m worldwide sales to date.
So basically, analyse all console sales starting from 3 months in from launch. After that point the platform fans have been satisfied and you're looking more at general, unprejudiced consumer interest.
I'm looking at previous console launch windows because they are most representative of the atypical circumstances in console lifecycles like supply chain issues and a dearth of new software. Unless I've made a math snafu of epic proportions, the Xbox One is selling much better than the 360, which launched in 2005 to critical acclaim, with no competition, with blatantly better technology showcased by PGR3, Madden, NFS, COD2, FIFA and Ridge Racer 6.
In comparison, the XBO launched under a cloud of Microsoft PR incompetences with day 0 competition in a cheaper, more powerful rival running multi platform games better. The early XBO had an unintuitive UI that forsake all the friendless of the 360 and make setting up multiplayer sessions painful.
I reckon it's doing ok. It's done the equivalent of run a four minute mile, where the track is full of pot holes and a sniper is trying to kill you
I also think the quality of first party exclusive content will be a big factor in how many multiconsole owners will eventually exist. But I think in that regard, by MS effectively going after exclusives that have an effective analogue on their competitor's platform (e.g. TR vs Uncharted, Forza vs GT etc), they're in many ways creating even less reasons for PS4 owners to pick up an XB1 as a second platform, since those gamers can simply play the competing franchise and be content that the game is similar. So in general terms I think the fact that the total console libraries being so similar between PS4 and XB1 works against the XB1; since it's not only proven the weaker console, but also the less popular one by a signiifcant margin.
You may be right, although I don't quite agree with like for like comparisons. Tomb Raider and Uncharted are only passingly similar games. They are both third person action adventure games but Uncharted is a core shooter with a bit of platforming and puzzle solving. Tomb Raider is not, even the 2013 which ramped up the combat, isn't as combat bevy as tomb raider and I anticipate Rise to return to the roots and be lighter on combat - based on what little Crystal Dynamics have said.
Similarly, Forza Horizon 2 and DriveClub. DriveClub looks very pretty but I'm more interested in what Forza Horizon 2 represents. I like the idea of being able to drive 'freestyle' in a massive open world and I'm not sure DriveClub offers that. And while some gamers may not be fussed if they play Uncharted or Tomb Raider, or Drive Club or Forza Horizon 2, I think there'll be plenty of gamers who have a distinct preference for a particular variation of a genre.
I have to conned that I was set on getting an Xbox One this Fall for the Master Chief Collection but the price of the 1Tb model along with the glimpse of Halo 2 campaign mode shown at Gamescom, which did not look great, has severely dampened my enthusiasm. I had a foot in Microsoft's yard, now I'm on their fence. I'm still certain I'll get an Xbox One but I'm less sure when.