I'd like to see the ability to drag in a .ISO DVD image and have it played.
VLC has this feature, from its wikipedia entry:
Another interesting feature of this player is the ability to use libcdio to access .iso files so that the user can play files on a disk image, even if the user's operating system does not have the capability of working directly with .iso images.
Obviously this is dependent on #27.
I don't know if VLC supports .ISO images besides DVDs.
#27, this and the other features slated for 1.0 would allow me to play at least 99% of my movie files through Perian (in particular through Front Row)
