This is undoubtedly good early news- now to see if the Xbox One X can sustain this momentum over the longer term.
The Xbox One X is a $500 machine, an upgrade to a relatively unpopular console, and one that isn’t even properly on sale yet (and in fact, only went up for pre-orders a few days ago). In spite of all of this, it has managed to outsell the PS4 Pro’s total sales for this year so far on Amazon in the US and UK (at least).
Coupled with Microsoft’s earlier assertions about the system selling better than expected, all of this points to the conclusion that the system may in fact be doing unexpectedly well- in spite of its high price, and Microsoft’s lack of exclusives.
Now, there are a few things to keep in mind here- it is important to remember that Amazon sales are not a 1:1 reflection of the larger market, you need to remember that this is limited to just Amazon, and in just two countries, and you need to remember that early sales are not indicative of long term success (after all, even the PS Vita and Wii U put forth a strong foot at first; it remains to be seen if One X would be more like those, or like the Switch, which has managed to sustain its success beyond its launch).
Nevertheless, even with all those caveats, this is conclusively good news- this indicates that there is still interest in the Xbox brand. If Microsoft capitalize on this momentum, they could conceivably begin to look at a recovery from where they stand at the moment.