Mavericks to include better window management solution?

Yes, Mavericks will keep the window in the same location as when you unplug your external display.

The only exception is when you take one of those windows full screen, in which case it will not return to the original position when you exit full screen mode. The window would instead go to your currently active display.

Using Mavericks Mac OS X 10.9.1 here with 2 external monitors and the laptop display on a MBP late 2011. One is connected via the thunderbolt port and the 2nd one via a USB external adapter/card. Mavericks does not remember window position and sizing after unplugging my MBP from the two monitors and re-plugging it. Still have to use Stay.