Comment 5 for bug 941227

So, the gsettings key mentioned by Mirco doesn't seem to exist, and the sesttings I see in gconf for notify-osd say "this key has no schema" when I select them in gconf-editor.

Beyond that, having it appear on the screen which has a focused window, is also never what I want; and certainly shouldn't be what happens when notify-osd is running other environments, such as Classic GNOME. Given the current multi-monitor support in Unity, which displays launcher, top panel, and all indicators, on all screens, it's probably best if notify-osd also appeared on all screens under Unity.

In any case, what I'd really want is to only ever have the environment chrome (panels, notifications, etc) on the primary display. I see no way to do that, with notify-osd, nor the rest of Unity.