Usability is a huge scientific field for itself. Many bigger opensource applications make some heavy (compared to previous practice) work on usability, including Gnome, Firefox, Fedora etc. I specially know a little of the efforts at Gnome.
I know it at code level only is a small part that is the GUI (or UI to take it more generally), but it is what that is needed know to make the masses use VLC now.
The player sounds to be able to play a lot, streaming, subtitles and on and on. But there could be done more work on the UI. Specially the settings are awfull to open as ordinary user. The playlist do miss some features.
Who (of the developers) are responsibly for the wxWidgets / Skins2? Is the mailinglists the main place for general development discussions?
If there doesn't exists, there should be created a UI group. That's just my opinion on the issue.