Do have to echo the whole 'lack of diversity' point, but to be fair it was more of an issue with the last few years of the Xbox 360 than it is (so far) looking to be with the Xbox One, as this time Microsoft is in a position that leaves them hungry to compete. That and they're no longer so focused on churning out Kinect games. Whether due to trying to shake things up, or perhaps become more competitive, Microsoft's showing signs that they might be looking to expand their roster, albeit with the sluggish course-change you'd expect when games can take three or four years to develop. Although, granted, a lot of said diversity so far is coming from contracted third party titles, but I'm hoping the third-party titles are actually a stopgap measure to give them time to build up their first party development capabilities, which would then be used to pursue a variety of gaming goodness. :3
However, I think the long-term question on whether or not that change of heart will maintain throughout the generation will depend on how these new titles are received; if Xbox gamers, (and I mean a significant number of them,) embrace quirky, non-traditional fare outside of Halo, Gears and Forza, then I believe quite strongly that Microsoft will see the good business sense in catering to those markets, leading to a wider variety of titles for all. ^^ If, on the other hand, too much of their market largely focuses on the few genres for which the Xbox brand became known, and titles outside that bubble struggle to find their place in terms of profitability or even attracting new gamers, Microsoft might eventually go back to maximizing profit by focusing their development efforts on what the bulk of their consumer base wants.
As for which one'll happen, I really have no clue. =P I don't pay much attention to multiplatform software sales between the Xbox One and PS4, so I don't know how well RPGs or other non-shooterbro-esque titles fare on both consoles. I also don't know Microsoft's mindset, and how long it will be before their thoughts turn from primarily focusing on expanding their install base towards maximizing profits from said install base.
Anyway, while you might have a point insofar as 'lookers,' I should point out that as far as first-party output goes, Sony simply has a reputation for offering more variety, one largely earned over the end of the PS3 and Xbox 360's generation. And that's excluding Japanese titles, which just dumps a whole bunch of OTHER exclusives on Sony's side of the fence, assuming of course you enjoy Japanese titles.
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Or He Procrascinates, In Which Case Zanten, Doer Of The Things Later
Or It Involves Moving Furniture, in Which Case Zanten, F*** You.