Whoops, my mistake.

Looks like this .deb file does have an icon for the home screen. It just unpacks to /usr/share/applications/hildon as if it was a Maemo package.

Move the /usr/share/applications/hildon/presencevnc.desktop file to /usr/share/applications after installation and the icon will show up just fine on the N9.

Another oddity is that that app (which only appears to work in landscape) disables the swipe UI while in the initial connection dialog screen.

Once a VNC session starts, you can swipe again. And you can always tap on File -> Quit to exit the app as well.