The trailer for FFXIII from the 2009 E3 show is live at GameTrailers. Game to be released in 2010. In a surprised announcement, Sony said FFXIV will also be released the same year!

So this must be why it's taking so long to release FFXIII. Square Enix was actually working on 2 FF games simultaneously! 

The PS3-exclusive Final Fantasy XIII game demo will last more than two hours, which is longer than the CGI movie bundled with it, Final Fantasy VII: Advent Children Complete. The bundle releases March 2009. Both on separate Blu-ray disc. Advent Children will look fantastic in HD. I will definitely pick this up on release day.