Public vs semi-public lists?

I've created several lists. Sometimes I'm given the option to make it public or semi-public, sometimes not. One list I labelled "public" keeps reverting to semi-public and I don't have the option under "edit" to change it back. WTF?

Any of your basic "favorite" lists that get created when you favorite an actor, director or musician will always be semi-public. If you want a non semi-public one you have to create a seperate custom list but then those people won't be listed on your profile under favorites. The lists created automatically can't be made public. It's a hassle, but I think it's so the site and feed isn't overrun with "favorites" lists. If I go to your homepage though and look at your lists I can see them, they just won't ever get promoted on the front page.

OK,..I actually recreated one of the lists (Favorite singers). I had the option to make it public, which I did, and AGAIN its reverted back to semi-public. This is stupid.