Different target group. I don't think it was ever meant as an Office replacement, but rather for the home user/very small business.I really want an updated feature-rich Office replacement in iWork '12. I have office 2008 and I do not want to pay through the roof for a multiple-license copy of 2011 (business).
I have MS Office 11, but rarely touch it. I can get more out of iWorks (and faster) - not a secretary though.