When Mike upgraded the board recently, the upgrade included a change to the "rep" system. A member cannot rep the same person until he/she has repped 3 other members. Also - rep points aren't worth 1 point any longer. Under the upgrade, the more rep a member has, the higher the value. So - in other words - rep ME because you'll most likely get triple the value in return.
This new system wasn't done on purpose - it came along with the VB upgrade.