1. Return of Start Menu: For many desktop users, though the iconic Start Menu was less intrusive and a better fit for their workflow. If Microsoft that changed nothing else in Windows 10, the return of the familiar menu would surely have won over many of those who had elected to give Windows 8 a miss.
2. New Alt+Tab: Switching between applications is something many of us do all the time. In Windows 10, Alt+Tab brings up an updated view of your open windows, with generously sized previews and labels with icons to help you more easily spot what you're looking for. There's also a new Task View button, which provides a clickable overview of all your open windows and desktops.
3.Multiple Virtual Desktops: Windows 10 is the first version of the OS to come with support for multiple virtual desktops. You can create multiple desktops, and switch and move apps between them with ease. It's convenient for those time when you're working with a particular group of windows, then momentarily need to get off and do something else.
4.Snap Assist: In Windows 10, this triggers a thumbnail view of your other open windows just click one to have it automatically spring up and fill the remaining space perfectly. Running two applications side by side becomes a awesome experience.
5. Notification Center: It is not in the Technical Preview, but the leaked videos of unreleased version of Windows 10 shows a new notification center.
6. Upgraded Command Prompt : This is not for everyone, but for the techies will love that the copy and paste works in the Windows 10 command prompt.