It was revealed that Yian Kut-Ku would be returning in Monster Hunter 4, scheduled for release in 2013. This news was greeted with great elation by the many fans of the Mr. Kut-Ku on the net.
Why would they ever consider not bringing in the Yian Kut-Ku? He's the official first wall of Monster Hunter.
Edit: And I recently bought MH3U for my 3DS and found that, indeed, Yian Kut-Ku is not in the game so I apologize. I must say I prefer Yian as the first wall over Barroth.