If it is not repeatable I wouldn't worry about it.
Tonight I had a real weird one ...... logging in to the desktop took ages ...... and when I got there X was using 1.9GB ..... yep ... of the 4GB installed.
Logging out and in again fixed that and I haven't seen anything like it since.
Thats about what I'm getting here, I've had abt 3-4 times that it's not made it past the splash screen and the one time that it did I was using what i would consider a boatload of memory. Logging out did not solve it, but booting into safe mode, typing exit and hitting enter and it came up normally.
Next stupid question would be which kernel, still using 26.38.8? Been wondering if a kernel switch might be in order...
EDIT:
Are you using the Calgary mirror? I've been hitting it for over a week with no updates, I switched mirrors today to one in OZ, got a boatload of updates. So switched to another mirror and got the same list...
Commit Log for Sun Aug 26 13:44:48 2012
Removed the following packages:
libgegl0.1_0
Upgraded the following packages:
apt-sources-list (1.0.1-2pclos2012) to 1.0.2-1pclos2012
desktop-file-utils (0.14-2pclos2007) to 0.18-1pclos2011
gdk-pixbuf2.0 (2.24.5-2pclos2011) to 2.26.0-4pclos2012
gimp (2.6.12-4pclos2012) to 2.8.0-3pclos2012
glib2.0-common (2.31.16-2pclos2012) to 2.31.20-1pclos2012
gnome-doc-utils (0.20.2-1pclos2010) to 0.20.10-1pclos2012
grep (2.13-1pclos2012) to 2.14-1pclos2012
gtk+2.0 (2.24.5-3pclos2011) to 2.24.10-1pclos2012
kde4-config (4.8.3-6pclos2012) to 4.8.3-8pclos2012
konsole (4.8.3-2pclos2012) to 4.8.3-3pclos2012
konsole-part (4.8.3-2pclos2012) to 4.8.3-3pclos2012
liba52dec0 (0.7.4-11pclos2009) to 0.7.4-12pclos2012
libattr1 (2.4.43-1pclos2009) to 2.4.46-2pclos2012
libcairo2 (1.10.2-2pclos2011) to 1.12.2-2pclos2012
libgail18 (2.24.5-3pclos2011) to 2.24.10-1pclos2012
libgdk_pixbuf2.0_0 (2.24.5-2pclos2011) to 2.26.0-4pclos2012
libgimp2.0_0 (2.6.12-4pclos2012) to 2.8.0-3pclos2012
libglib2.0_0 (2.31.16-2pclos2012) to 2.31.20-1pclos2012
libgtk+-x11-2.0_0 (2.24.5-3pclos2011) to 2.24.10-1pclos2012
libgtk+2.0_0 (2.24.5-3pclos2011) to 2.24.10-1pclos2012
libpango1.0_0 (1.28.4-2pclos2011) to 1.29.4-1pclos2012
libpango1.0_0-modules (1.28.4-2pclos2011) to 1.29.4-1pclos2012
libpixman1_0 (0.24.0-1pclos2011) to 0.24.4-1pclos2012
libqt3support4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtclucene4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtcore4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtdbus4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtdeclarative4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtdesigner4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtgui4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqthelp4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtmultimedia4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtnetwork4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtopengl4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtscript4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtscripttools4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtsql4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtsvg4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqttest4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtwebkit4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtxml4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
libqtxmlpatterns4 (4.8.2-1pclos2012) to 4.8.2-2pclos2012
librsvg2_2 (2.32.1-1pclos2010) to 2.34.2-2pclos2012
libxfs1 (3.1.7-1pclos2011) to 3.1.8-1pclos2012
pango (1.28.4-2pclos2011) to 1.29.4-1pclos2012
python-qt4 (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-core (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-declarative (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-designer (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-gui (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-help (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-multimedia (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-network (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-opengl (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-phonon (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-script (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-scripttools (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-sql (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-svg (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-test (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-webkit (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-xml (4.9.2-1pclos2012) to 4.9.4-1pclos2012
python-qt4-xmlpatterns (4.9.2-1pclos2012) to 4.9.4-1pclos2012
qt4-common (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-database-plugin-mysql (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-database-plugin-sqlite (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-designer-plugin-qt3support (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-designer-plugin-webkit (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-qtconfig (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-qtdbus (4.8.2-1pclos2012) to 4.8.2-2pclos2012
qt4-xmlpatterns (4.8.2-1pclos2012) to 4.8.2-2pclos2012
turtlebeach-firmware (1.0.24.1-1pclos2011) to 1.0.25-1pclos2012
uClibc (0.9.30.1-5pclos2010) to 0.9.32-2pclos2012
wallpaper-theme-default (1.0-2pclos2012) to 1.0-3pclos2012
wget (1.13.4-1pclos2011) to 1.14-1pclos2012
xfsprogs (3.1.7-1pclos2011) to 3.1.8-1pclos2012
Installed the following packages:
libgegl0.2_0 (0.2.0-2pclos2012)
libjasper1 (1.900.1-1pclos2012)
libuClibc (0.9.32-2pclos2012)
Sadly something broke/futzed up VLC along with the updates.

jan