I think this is a very good idea - especially for new people trying to find a "starter" skin to get them going. It does need some careful moderation and planning but I think it could work well.
Personally (and this is just my tuppence worth) I think a mixture of suggestions from LS and JohnWPB would make the best solution.
Firstly potential skins are presented / discussed etc in the normal skins forum. Once they are "completed" or judged ready to release by the author, they can request to have the thread moved to the new "Released Skins" forum by the good Enforcer
who would perhaps also update a single list of "Released Skins" available as a sticky on the top of the new forum. This way we have a single (easy to read/navigate/find) list of released skins linking to the relevent threads in the same new "Released Skins" forum. To be released the thread must have as it's first post a screen shot of the skin, a list of it's working features, and a link to download it - not sure about having version numbers. The thread name should only contain the skin name. Relies should be allowed in the new forum but no new posts. And replies need to relate to that skin only ... no hijacking of the threads for other type questions ... this is where there needs to be a strong moderator available ... Are you still interested Enforcer ?
For a skin to be considered "Released" it needs as JohnWPB said, a main menu, audio player & browser and video player & broswer. All other functions should be optional extra's and I'm even starting to think that the video player & browser may even be optional as most people start off just wanting to manage / play their music collections !
Anyway ... that's my take on the plan ... and I did also vote !