Today I read at "http://www.apple.com/osx/preview/";
==============
Multiple displays
Do more on this screen. And that one.
OS X Mavericks takes full advantage of every display connected to your Mac, giving you even more flexibility to work the way you want. There’s no longer a primary or secondary display — now each has its own menu bar, and the Dock is available on whichever screen you’re working on. You can have multiple app windows running on either display. Or run an app full screen on each one. Even show a desktop on one display and a full-screen app on another. Mission Control can give you a bird’s-eye view, making it easy to drag what you want where you want it. You can even drag it across the room, because now AirPlay and Apple TV can wirelessly turn your HDTV into a fully functional display.
===============
If you can make an app go full screen on a monitor and continue to use the other monitor(s) independently, then I too will be pleased that this has been addressed. If there are additional monitor/display features that speak to power users' needs then I will be doubly pleased.
In effect Apple will have fixed a "bug" or "downgraded display funcitionality" that Apple itself introduced to use (imposed upon us?) with successive OSX updates (10.7.x & 10.8.x). That's what I was looking for.
If, as SebCorbin says above, it will cost me US$29 to obtain this fix I will not be so pleased. Granted the cost is nowhere near the cost of a Microsoft Windows OS Upgade.
Still, I believe I should not have to pay for a fix to a problem I flagged with Apple Care some time back (as did many, I understand). Now that the fix has been announced, Apple Care should, I think, provide it to me at no cost.