On questions that are marked as a duplicate of another question I think it would make it a little clearer if the link to the original question was in the "closed as exact duplicate" box as well.
This is just because I'm newish to the site and thought the "possible duplicate" quote was a question the poster was asking about his own question, and I was more interested in looking at the question it was marked a duplicate of first.
This would also fix the issue mentioned here I found before posting this: Closing as exact duplicate: Missing links to the duplicate questions
Edit: Thanks to Cody I have a better understanding of how this works. My confusion stemmed from the fact by placing the proposal of duplication in the question body that this was not part of the standard process for marking a question as a duplicate, then later thinking that the two messages appear at once when marked as duplicate by a moderator. I can understand the idea of placing it in the question body because people are more likely to see it when reading the question then some surrounding location. So an alternative change that would prevent confusion for me at least, is change the top message to "Marked as possible duplicate by Dave" and the bottom message to say "Confirmed as duplicate by Peter" then at least it's a lot more clear the two messages are linked, and that the link at the top is the official question it was marked a duplicate of. It also makes it more clear how the process works which is helpful to newish users like me.