Forum profiles have been slightly enhanced. It is no longer possible to include MSN or Jabber contact methods. Twitter and Google Talk have been added as contact methods. It's now also possible (but not required) to add your IGN to your profile. It will also be displayed next to your posts, like your modpack of choice.
Aside from the listed profile changes, the introductions board was added. Note that posting in this board will not count towards your total post count.