Smart is not beta, the first stable has been released and I used it without problems. I think it could work as the only package manager, doing everything including updates in hoary. There is already a kde applet that does this and ubuntu could use the code they have developed to make a gnome applet.
I WILL SAY THIS AGAIN, WITH BOLD AND CAPS, YOU ARE NOT GOING TO INSTALL FEDORA PACKAGES IN ANY DEBIAN AND GET AWAY WITH IT, THIS IS A REALLY STUPID THING TO DO.
But I really think that using it in ubuntu would give an advantage to the hole system package management. I really does the things apt should be doing, but in a clean and portable (but not hybrid (this second level parenthesis is to remind everyone to not mix apt-rpm or yum channels in an Ubuntu dist)) solution, and the update applet could be used by others distributions helping the hole linux community.