Binary package hint: compiz
I have an up-to-date i686 gutsy install on a Dell XPS M1710 laptop with an NVIDIA GeForce Go 7900 GS, except with some packages installed from hardy--specifically, the NVIDIA drivers. When compiz is turned on, I frequently see a couple different types of visual corruption of window title bars, some of which is new to the 169-series of NVIDIA drivers (i.e., does not occur with the version in gutsy). The corruption can be triggered in several different ways: (1) change of window focus (easy to see with UNIX-style focus), (2) mousing over the buttons at the top-right or the one button at the top-left, and (3) change of window title (e.g., changing tabs in Firefox). The corruption can broadly be categorized into one of three types: (1) sometimes the title bar becomes grey, perhaps with the title and/or one or more buttons disappearing; (2) sometimes the title bar becomes a translucent red or a translucent blue; and (3) sometimes the title bar disappears entirely (except for the one button that the mouse is over). Prior to upgrading to the drivers in hardy, I only observed the first of these.
The corruption occurs with all of the themes that I have (which is just the default ones that come with Ubuntu), but it is much more common on Clearlooks-based themes (particularly Human). Additionally, on non-Clearlooks themes it is situation-dependent, in that in may only occur in specific ways on specific windows for specific periods of time, whereas on Clearlooks-based themes it repros very reliably. It is also far more common for it to happen on maximized windows than on non-maximized ones.
Note that there are at least a couple other open bugs that are very similar: bug 99508 and bug 152493. The key differences are that I see a wider range of corruption modes and that I also see them on non-Clearlooks themes and non-maximized windows, whereas the others are apparently exclusive to maximized windows on Clearlooks. (I originally reported my issues in comments on bug 152493, but I have been requested to file separately.)
Currently I am using NVIDIA TwinView, but I have seen this both when it is on and off.
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=7.10
DISTRIB_CODENAME=gutsy
DISTRIB_DESCRIPTION="Ubuntu 7.10"
$ apt-show-versions | grep compiz
compiz-gnome/gutsy uptodate 1:0.6.2+git20071119-0ubuntu1~gutsy1
python-compizconfig/gutsy uptodate 0.5.2+git20070912-0ubuntu1
libcompizconfig-backend-gconf/gutsy uptodate 0.5.2+git20071010-0ubuntu1
compizconfig-settings-manager/gutsy uptodate 0.5.2+git20070912-0ubuntu1
compiz-plugins/gutsy uptodate 1:0.6.2+git20071119-0ubuntu1~gutsy1
compiz-fusion-plugins-extra/gutsy uptodate 0.6.0+git20071121-0ubuntu1~gutsy1
libcompizconfig0/gutsy uptodate 0.5.2+git20070919-0ubuntu3
compiz-fusion-plugins-main/gutsy uptodate 0.5.2+git20070928-0ubuntu2
compiz-core/gutsy uptodate 1:0.6.2+git20071119-0ubuntu1~gutsy1
compiz/gutsy uptodate 1:0.6.2+git20071119-0ubuntu1~gutsy1
FYI, I have switched to Emerald based on a suggestion by a user on bug 99508, and the problem does not occur (not even with the "legacy" engine), so this bug no longer affects me.