I think two of the more impressive aspects of Facebook's growth - and Zuckerberg surely had a strong hand in both - was how smoothly the site scaled to accommod

I think two of the more impressive aspects of Facebook's growth - and Zuckerberg surely had a strong hand in both - was how smoothly the site scaled to accommodate the very rapid network effects, and how relatively uncluttered the site remains. Those both take a tremendous amount of knowledge and discipline that he couldn't just cruise through on.