Regarding Zack & Wiki again, I found this thread at Capcom's forum:
http://www.capcom.com/BBS/showthread.php?t=25019&highlight=zack+wiki+sales+expectations
It's not conclusive but it does seem like Z&W has already hit their expectations (and it continues to sell, I bought it yesterday for example :P).
My Mario Kart Wii friend code: 2707-1866-0957