Comment 14 for bug 1003100

Direct removal of ttf-mscorefonts-installer wishes to remove ubuntu-desktop update-notifier. I figured I've been stuck with a broken set of packages for about a week now, and I´m wanting to fix that.

Ran:
sudo aptitude remove ttf-mscorefonts-installer

Indicated Yes when it presents the solution as including a remove of ubuntu-desktop, went ahead and allowed it to proceed with the recommendations. This is the nasty bit of this bug that seems to indicate you are forced to remove loads of stuff to suit this one package.

Only then could I proceed to install update-notifier. Once that occurred, it seems to be a well working fix. Never having run into this error would've been the best situation though as packaging snarls like this make me kick myself for perhaps upgrading too hastily.