That is great news! There are lots of upgraded features as well as bringing back the start button. Among other things what Microsoft realized is that the main feature that people hate about Windows 8 is that the start button is gone. (Side note if you want it back on Windows 8 let me know. We have a program that will add it back)
What else is new? Lots!
1) Universal apps. Now the exact same app will run on your computer, tablet or Windows phone
2) Cortana. This is Microsoft's version of Sirri and looks like it may be a serious competitor. As everything else you will be able to use the same tool on all devices. Phone, computer or tablet.
3) Spartan. A new browser desperate from internet Explorer with a much cleaner look and lots of mark up tools so you can actually highlight and mark things on a website to share with others.
4) Continuum. Now when you have your tablet in desktop mode the apps will run in windows but, when you un-dock the computer, it will automatically change to full screen mode.
5) Gaming. Now you will be able to steam any Xbox One game to any Windows 10 phone PC or tablet.