So like the commenter above I think it's not a problem specific to -intel. Think this is the same as bug #708749 which is -nvidia. That user also found that killing metacity made the regions go away. So I think it's not an X issue at all, but I'll leave it open against xorg-server until it's more definitively understood.
Think I'm seeing this same behavior from time to time, on an -ati system. In fact I reported it upstream as a driver bug before finding this report:
https:/ /bugs.freedeskt op.org/ show_bug. cgi?id= 36699
So like the commenter above I think it's not a problem specific to -intel. Think this is the same as bug #708749 which is -nvidia. That user also found that killing metacity made the regions go away. So I think it's not an X issue at all, but I'll leave it open against xorg-server until it's more definitively understood.