I would say, the good things about xbox one
a better Microsoft ecosystem, you know, now apps will be available in One, and they are probably going to be like win8 ones since they said like people should start by learning to build win8 apps to know how to build for xbox one. so more access to you, for example, VLC when finally its ported to win8, well maybe it will get into xbox one, and then people can play mkv and formats Microsoft probably wont directly support. and I expect to see apps in xbox one just like you see plugins in xbmc or plex, just to make the experience better.
another nice thing about xbox one its Kinect 2, a lot of games will use it. project spark being free, will use it for example, and you can record your movements and sound and stuff like that. they know everyone will have it, so they are making nice things with it, if people want it. but it can be used for a lot of things, since it can detect a lot of things like your heartbeats and who is holding the controller and your expressions and such.
also Kinect would be better through the system because is built to take advantage of the UI and the OS, not like 360 that was limited in a lot of things.
smartglass apps will be useful this time, hopefully we finally see the coop gameplay they showed once with a tablet and xbox. if its true the delay is now decent, well... that means it can be used for more things, that's what all we wish at least!
cloud, maybe its not something that many games will use, but something like what forza is going to do to make it more realism when you compete against IA, its a nice thing. so cloud can make the console more interesting because you aren't going to be limited anymore, you will be only limited for what a developer can do with it.
just look at achievements, for the way Microsoft its building it with cloud and all that, achievements are supposed to be able to be updated by developers, so they can add new challenges for you without you having to get a new game.
so cloud can make the console evolve and grow, without updates from Xbox team.
Skype integration would be a plus! and well... all the multitasking features, like you can be matchmaking a game while playing other. and in the video leak that was posted sometime ago, you could go to start while the game was playing so you didn't have to see the cutscenes and do other things while waiting. also it was instant how the game started.
maybe these don't sound like few things, and it doesn't mean you should buy xbox one right away having 360, but more and more features would come, especially when xbox team has to make nice updates yearly. so of course it will be a better integrated ecosystem among Microsoft products than 360 was.
of course we shall wait and see what else Microsoft brings with Xbox One, but I think its a nice upgrade over 360 in a lot of things.