Play as infected in the demo

Here we go
http://forums.steampowered.com/forums/showthread.php?t=1008519&page=4
this one even has lots of pics
http://img230.imageshack.us/gal.php?g=c5m1waterfront0002.jpg

But... He does not tell a thing. Though he said that he WILL tell us how. Maybe even today.