I think it’s nice idea, everybody will be able to show their images in tweets if they use for instance twitpic API for all their content. Like on facebook, but you will have the same control as now, you will not show everything like facebook does if you don’t want to.
This will allow whole new opportunities for media.
I’m thinking about images because I would like to show images on http://openclipart.org/ when someone tweet a link to it, so I could upload that image to twitpic and put a meta tag like
and twitter will process that.