according to an ign article after psx they are well past the half way mark..
https://twitter.com/ChineseRoom
some interesting new tweets
No idea if the game is near completion or far though
http://me.ign.com/en/playstation-4-gaming-hardware/99458/news/everybodys-gone-to-the-rapture-dev-discusses-non-l
im sure well get more at e3