While Songbee does not intend to compete with some of the more established projects mentioned above, the following features are anticipated in future releases:
Ability to select alternative song databases
Drag-and-drop interface to adding songs to the playlist
It is unlikely that Songbee will support display of Powerpoint or multimedia files, but Powerpoint can be run at the same time as songbee, and if you start a powerpoint show it will open over the top of songbee's output.