I think there's been something of an overreaction to the whole XBox One vs PS4 debate, but before I cover it I just want to add that I'm not buying either console; I'm just going to wait a while and build a small form-factor PC to a good gaming standard with whatever decently priced parts I can get.
Anyway, the big issue with XBox One is digital versus disk; for the XBox One the disk is used purely as a means of installing the game, you don't need the disk once it's installed (though it can't hurt to keep it). So what Microsoft is doing instead is providing a platform for authorising your digital content across accounts and XBoxes, which
in theory is actually less restrictive than for the PS4 as you can share with up to 10 people (I believe in addition to local accounts on the same XBox which can just play normally), and there is some kind of system on the way to de-authorise accounts so a game-disk will be able to be resold*. The main issue is that this will be a platform rather than a strict contract, so it's up to the publishers which capabilities they will enable and to what extent. However, the thing to take note of that this is no different from now, as publishers can (and many do) already add DRM to their games that add restrictions to resale and lending, such as unlock codes to enable exclusive content for only the original owner of the disk, or anyone willing to pay for a new code.
The systems may seem very different, but in practice they're going to be pretty much the same, as both leave it up to the publisher. The main difference is that the XBox platform is all about digital without being tied to disks, which is pretty much the way things have been going anyway.
*For resale on the XBox One, I fully expect the system is already in place, it'll just be a matter of rolling it out to trade-in stores so they know how to verify or de-authorise a game before resale (so you don't end up with an unusable disk).
Regarding the price; I was pretty shocked at the $500 figure for the XBox One, as that's PS3 release territory, but it does come with TV capabilities and a bundled Kinect, so it's not like you're not getting anything for the extra $100. The main issue with the price is that on paper the gaming console side of the XBox One comes with less hardware; it has essentially the same CPU, but its GPU is around 1/3rd less powerful, although it has 8gb of RAM 1-3gb of that is for the non-gaming OS. Spec-wise the RAM seems worse as well as the PS3 has 8gb GDDR5 while the XBox One has DDR3, but there are differences there too; GDDR5 has great bandwidth but poor latency, so while it's great for a GPU it's not so good for more general operations, though this may mainly affect physics but otherwise shouldn't be a big deal for gaming. So for $400 you get a better pure games console, while for $500 the XBox One is still plenty capable for a games console, but has a heavy aim towards TV as well.
I dunno, it's an interesting pairing, but personally I think we've still only heard a fraction of the exclusive titles that Microsoft will be lining up, and this where they will regain a lot of ground as you can never underestimate the Halo effect of… Halo