i'm using an nVidia video driver that works well. also, the icons are fine, one of the 1st things i checked. also, it doesn't matter what icon/program/applet is in that corner they all do it
after monkeying with it some more, i'm inclined to believe it is a gnome-panel error. check this out:
new screen
this shows the panel moved to the bottom of the screen. the mozilla window is maximized, yet will not extend up past the panel's position before it was moved. also, the missing pixel problem does not occur with the panel on the bottom, as shown above.
finally, this screen (and i'll stop posting them after this one, i promise):
final screen
the panel is on the right, and in this position both problems are visible. the mysterious missing rectangle appears and windows cannot be fully maximized. i think i will also send an email to gnome.org about this as well.
scott