I like the basics of this idea. Maybe, on the update page, a 'post link' button that lets us paste a URL that then autofetches meta and codes it, but that we can then edit after it's done the code?

I doubt I'd, personally, use it a huge amount as I code everything, but I can see it being useful for those that find coding hard, annoying, whatever and thus useful for me to see it.

G+'s linksharing is particularly impressive as it goes to fetch a chunk of stuff including the favicon for the page--I'm less impressed with the way it just picks a random picture, Facebook's let you pick the image thing is better on that (links to my journal always pick my sidebar mugshot first, I've no clue why, I want the post icon damnit!)