Sure enough, it appears the hacker did this in tribute of Facebook CEO Mark Zuckerberg.
The clearly unintentional welcoming message on the website homepage (the rest of the site seems to function fine) currently reads:
“Got in and all i could think about was zuckerberg!!! This’ for you Mark!”
(Click the image on top for a larger version, just in case things get fixed)
Amusingly, the title tag for the page has also been ‘updated’, now reading “I’m CEO, BITCh!” (see here for the backstory on that).
Setting a trend for website defacement in 2011?
Update: it now reads “OK. Its not that big a deal! :P”.