Apparently, Yahoo has stopped moving ne messages to the top of the list and has discontinued Noting the "Latest Post" with the name of the poster. I found this at this site.. (Fill in the obvious blanks) also see below the link.
"Lots of folks posting on the boards had no clue that the removal of the bumping feature was an intentional change. They are not happy with this change just like me. I couldn't link them to this site though since links are not permitted in the Yahoo Finance forums. "