I noticed there are mit and mit-license, but (as both the tags don't have a description) I am not sure I understand when to use one, and when to use the other one. As I noticed there are gpl and lgpl, I thought that the tag for the MIT license should be mit; when I entered "mit," the autocomplete proposed me both mit and mit-license.
Probably just a case of mistagging. I'm looking at the licensing tags and they're a mess.
I'll see about coming up with a clean-up suggestion. I think something like "license-X" would work well, cause it'll support wildcards in tag favourites, but for now I'd say it doesn't matter which one you use and we'll settle on an approach in a couple days.