After seeing the e3 conferences it became clear to me that Xbox one and Windows 10 have some amazing sinergies and that it will only get better. It is slowly becoming a single ecosystem which is amazing to see. 

Few features that Win10 and XOne will share:

1. Xbox One and Xbox 360 game streaming to any Windows 10 PC - allows you to decluter your livingroom and enjoy entertainment through a single device plugged in to each TV in your household

2. Oculus Rift, Steam VR and other VR gear designed for PCs appear to be getting Xbox One support through the PC

3. Xbox One controller is becoming the de facto controller for PC, much like Xbox 360 controller before it

4. DLC, mods and cross platform purchases and play between Xbox One and PC are slowly becoming a reality 

5. A lot of Sony console exclusives appear to be hitting PC as well, giving PC gamers access to best indie games found on PS4, and upcoming PS4 big hitters like SF5 and Shenmue III

Next steps in this evolution should be to allow PC game streaming on Xbox One, which will surely happen eventually. Finallly a unified game store and library across platforms is inevitable, but may take some time to become a reality. 

How long until one can buy a Windows 10 gaming PC with minimum spec requirements, and have their whole Xbox One and Xbox 360 gaming library accessible to them? 5 years is my bet. 

People were right when they said that this will be the last console generation, because PCs will take over after this. 

I haven't read much about it, but Windows 10 is coming to XBO right? Would it then be possible for Microsoft to open the system up to allow XBO to run PC/Steam games (no streaming required?) That would be a pretty big bombshell.

Never been a huge Xbox fan, to be honest but this is very good news for me as well since it means that PC will get more and better support from more mainstream developers.
They should capitalize on the recent growth in the PC market and make a comeback here (MS, that is).

Still a sad joke that MS are having to play catch up with Sony in Console/PC cross play. SMH

But yes its all good news.

sure, if it's a pre built pc with the playstation logo on it then yes.

Knowing Microsoft, I don't know if they will ever allow that. Streaming? Absolutely...but not natively. Just like Google doesn't allow apps to be bought outside Google play (legally) and Apple doesn't allow apps to be bought outside Apple store, MS can't allow a competing ecosystem to sell games on Xbox natively.  

With that said, I can see Xbox becoming a game platform over time that lives everywhere and in other app stores. Android, iOS, Windows Phone game streaiming? Why not?

With Balmer gone, looks like Microsoft is back in the business of selling software and cloud services.

I see. Maybe in a future platform. I can see the next generation or two being almost a spectrum of open-platforms to closed-platforms, with Sony and MS transitioning to mostly having software-based platforms and creating their own unique hardware for exclusives while allowing other PC releases to run on their platform, and Nintendo being strictly closed platform. Kind of like if they all created steam boxes  and limited the hardware on which their exclusive games can run. It definitely seems to me as if console gaming and PC gaming is merging as it becomes cheaper for small PC form factors and PC gaming becomes more convenient and popular. If Microsoft allowed steam to run on their platform, even in a limited form, that would be a huge step toward this. But like you said, that would give their market to their competitor (Valve.) 

The new Xbox One dashboard looks a lot like the Windows 10 app.

I think that sounds right.

You know there is one easy solution to this cross platform play competing store issue. Microsoft could just buy Steam. :)

Help me out here: going through your list, why wouldn't I just skip the Xbox then?