Punch Out!! – More to be revealed?

This is straight out of a Punch-Out!! preview from ESPN Games:

And multi-player isn’t even the last new feature to be announced for the game as Nintendo promises another surprise to the title once it ships to stores May 18. What will it be? I guess we’ll just have to wait a few weeks to find out. Until then, all I have to say is, the more I played the new “Punch Out!!” the more I really enjoyed it.

Aside from new fighters, I can’t really think of much else that could still be revealed aside from perhaps a Wifi mode or leader boards, both of which are very wishful thinking. Thoughts or speculation?