Yup, me too, but I might have stumbled across a functional work-aroud: Turn off scaling.
My Mac Mini (2012, 10.8.2) was exhibiting analogous behavior on a target headless Mini (2007, 10.7.5) - though for me what happened was windows drawing in the lower-right corner of the shared screen, and I couldn't seem to drag them anywhere.
Also, hitting cmd-n to open a new window in the target system's shared screen did nothing. Or at least, nothing visibly changed. The target system is being used as a media server. As such it has a minimal system install.
I set the screen sharing prefs so dynamic scaling was off, and to scroll the screen when the mouse gets to the screen edges in the screen sharing window (see the screenshot for the settings I'm using now). After a reboot of both systems, that seemed to solve the problem.
I was also having redraw problems at first (a black shared screen), but clicking the Dashboard icon in the dock forced a screen-wide redraw.
Hope this helps!