One of the things I am missing in Linux from my Windows days is a unified media player app that can keep an up-to-date list of all my audio *and* video files in a given location, and offer me the chance to play any of them. With its mplayer back end, KPlayer is a perfect candidate for this. However, I really don't want to have to add the hundreds of files and directories that I already have to KPlayer manually. I also don't want to have to remove them if I delete or move them around.
Several packages already have this ability to watch directories for music files (Amarok, Rhythmbox are two examples.) I'd love to see KPlayer do this for all supported file formats.