This.
I'm pretty sure I voted to undelete a question a couple of days ago (and another one today). Apparently, neither of them have been undeleted yet, since the last undelete vote shown in my profile is from March last year. I'd kind of like to go back and see if anyone else has agreed with my vote, but I can't, since there's no link to the post in my profile!
If I'd flagged the post for ♦ mod attention instead, I could've found the link to the post in my flag history. If it was my own post, I could've found it under deleted recent questionsdeleted recent questions. But since I just voted to undelete it, there doesn't seem to be any way for me to find it again.
I'd very much like to see this information shown, at least when viewing your own profile.