It turns out that when a post has been moved, clicking on A Forum's "Last Post" (which has become a pointer)
What's shown in the Last Post column is not the pointer. If you go to the Mac OS X Applications forum now and compare the URL for the "Time Outs With Safari" pointer there you'll see it's not the same as the URL of the Last Post on the main index.
It's a "pointer" in the sense that clicking on it takes you to the new location...not in the sense in which you originally used it. (I guess I could have used a better word.)
Edit: But, yeah, this is new behavior, although I can't date it.