I have just installed the devel channel on a Nexus 7 and I want to remove multiple pre-installed apps so that my "apps" list only contains launchers for apps that I want on my device.
Just long press the app you want to uninstall, now it opens Ubuntu store where you can select uninstall.
For the shortcuts from the side-menu long pressing also gives the option to remove the link, thought that is not the same as a uninstall.