Craig Ferenghi just announced some features OS X 10.9 Mavericks:
• Finder Tabs. No more having a thousand Finder windows open. Now it’ll work like Safari with one tab for every Finder instance. You can
• Tagging. You can now tag files to make it easier to find files you need. These tags exist almost as smart folders in Finder, and you can easily tag files by either entering the text you want to tag it with, or drag them into your tag folder. Looks like Apple has finally given up on hiding the file system on OS X.
• Multiple Displays. Finally, proper multiple display support! Going full screen on one display won’t blank out your other display. And you can pan Spaces on each display individually. You can easily open apps on whatever display you want, have more than one app fullscreen at once (dragging assets between apps) or keep one display static with pinned apps (like a Dashboard) while you work dynamically on the other one. You will also be able to use your Apple TV as a second display over AirPlay.