Here's a quick hack to use the Natty version (at least until an Oneiric version is released). It seems to work as per usual.
The second-to-last line reinstalls apps that were removed with notify-osd at the start.
The aptitude command at the end locks your version of notify-osd from being 'upgraded' to the official Oneiric version (you'll obviously need aptitude installed if you wish to run that line - sudo apt-get install aptitude).
sudo apt-get remove notify-osd
sudo dpkg -i notify-osd_0.9.30-0ubuntu4-leolik~ppa1-1_i386.deb
sudo dpkg -i notifyosdconfig_0.1-6~natty1_i386.deb
sudo apt-get install gnome-power-manager ubuntu-desktop update-notifier
sudo aptitude hold notify-osd