I have been a loyal user from 5.0 to 6.0 to 6.1. Moving from 6.0 to 6.1 was traumatic and I still don't think it is where it should be. Using a BT headset and Voice Command a MSFT product did not work under 6.0. It is better now but not as good as under 5.0.
1. Make the interface faster (like you are doing moving from Vista to 7. 2. Either build in the voice command software or make sure it works. 3. Make sure that applications like Walking Hot Spot work making your smartphone a wi-fi hub (or build it in). 4. Make sure hardware companies add more memory - both for storage and program operations. 5. I read about a tweak that allows significantly faster internet speeds.
If you want to smoke the other platforms you need to unleash the power of WM. I see many intentional limitations. Certainly we would like a system more like Apple's iPhone in terms of useability but I think you can beat them by producing a cleaner and faster application.
Traveling with a laptop and being able to connect with fast Internet speeds wirelessly through the WM device would be killer.