You're right, I don't know why I expected a UI overhaul. It seems as though Win10 has most of it's meat under the hood. Integrated hyperV, some sort of separation of personal data and application data via hyperV? virtual desktops, and in general just better control over the OS. Have you noticed anything else in particular since using the preview edition (aside from UI elements)?
Windows 10 is a pretty monumental release in my opinion...
The start menu is being re-written as a "modern" app deployed via store using the windows-app-store-model .. It's using new WinRT composition api's to deliver a "Continum" app that has multiple UI's that morph into each other as you go from desktop -> tablet -> mobile ...
There are several other completely re-written from ground up modern apps that , as above, use the app-store-model to deliver themselves.. These will replace existing windows apps/services eg. music/video/media/xbox apps etc all have new re-written apps..
We will get a new browser architecture, that builds ontop of the old BUT is a dual-architecture (EDGE) .. It reworked the trident and chakra engines, new dll's of each will exist going forward and the old ones will remain for backwards compat ..
- Trident - MSHTMlL.dll (legacy) / Edge.dll (living)
- Chakra - Jscript9.dll (legacy) / chakra.dll (living)
This new browser architecture will allow the "living" side to innovate faster .. Also a new UI written ontop of these engines, which is code named Spartan, is as the other apps mentioned above , will be a windows-store-app-model app .. It will be deployed via the store and can be regularly updated as such..
Under the covers within the OS the biggest change I see happening is Windows will get a "Container" technology. Ill call this the WindowsContainer. This is similar in concept to docker and Linux containers BUT it's also very different in it's overall goals..
This is a great intro to the concept of the "
Windows Container" , theres still not much known about it BUT its a start..
There's also so much going on in the developer front ... WinRT vNext, a lossening of the window-app-store sandbox to allow a great range of apps (rumors that more win32 / 3rd party framework love coming)
.NET Native for us .NET lovers ... lots of news already out there in the public domain regarding the importance of this ...
DX12, I don't need to say much on this as you can go to the public announcements and videos on channel 9 ..
And the biggest news is of course that Windows 10 (Threshold) is rumoured to be the ONE OS that will span embedded/phone/tablet/desktop/console/server ... same exact WinRT api's , Dx12 , Trident/Chakra engines that span the entire ecosystem so devs can build "Universal Apps" and have the confidence the underlying api's and engines they rely on will be consistent across windows ..
And of course with MS's latest moves going Open with lots of it's dev stack, hopefully we'll see some x-plat love for Dx12 and WinRT .. Would love to be able to target a "universal app" and have it compile to iOS/Android .. I know of Xamarin and Fuse BUT MS have WinRT/Dx12/.NET native .. I would love to see them take the big step of doing this..
sry for the long winded post BUT been following lots of these techs for years, many since research (drawbridge/midori etc) ... really excited for Win10