If I'm browsing /unread, I want to see the text of the first new message in the thread. That will give me a clue as to what the conversation is, and how it is progressing.
Seeing the last posted message tells me nothing, since the conversation will have gone well past the last thing I read in that thread.
Especially since clicking the link takes me to the last read message, so I have to scroll down a bit anyways to find the first unread message. If /unread showed the preview of the first unread message, I could "preload" that into my brain, and have a clue as to what I'm looking for.
If I'm browsing /unread, I want to see the text of the first new message in the thread. That will give me a clue as to what the conversation is, and how it is progressing.
Seeing the last posted message tells me nothing, since the conversation will have gone well past the last thing I read in that thread.
Especially since clicking the link takes me to the last read message, so I have to scroll down a bit anyways to find the first unread message. If /unread showed the preview of the first unread message, I could "preload" that into my brain, and have a clue as to what I'm looking for.