Continuing the discussion from Unicode roman numerals: Is there an official stance?:
I’ve wondered before about this. How could semantic meaning be embedded in titles? I mean, there are times when it would be pretty cool to have e.g. italics in a title. wouldn’t there?
So. Maybe this is dumb. But what if there was an new alias type that accepts semantic markup? I don’t even know what that would look like. Something xml-based?
I dunno. Just a thought.
It seems to me that, unlike Roman numerals, italic is presentational, not semantic.
Well, sure. I’m not saying I want an <i> tag. Do those even exist anymore?
There are lots of places that one might want to apply custom presentation if the titles had semantic markup, aren’t there? Of course, none of them come to mind right this minute because that’s not how my mind works. 
Maybe you want to have dates for live bootlegs displayed differently. Maybe you want super-work titles in italics, or omitted entirely.