XB1 didn't exactly go as well as they planned. It's a good name if your a customer who understood and wanted the XB vision of an "all in one media entertainment device", but a bad name if your expecting a dedicated game console, which also probably means you know this isn't the first XB console.
XB3 wouldn't have been a good idea, but skipping 3 and going to 4, just like how they skipped from 8 to 10, would have worked. XB4 vs PS4.
They also could have kept the 360 type name and used 420 or 540. Both would have felt on par or superior to PS4. Now 420 may not be a number that XB wanted to associate with itself, even though it would make sense with the green XB color scheme lol. I can also see why they may not want to use 720 either, since it's supposed to be a 1080p machine.
This is why really thought they may go with XB 1080, since it was supposed to be a true 1080p machine. It would have fallen into the 360 naming scheme perfectly, and would have had 10 in the name to match with Windows as well. Maybe since XB knew many of the games weren't going to actually be true 1080p, especially at launch, that they decided to try an avoid that as well.
