I found this while waiting for the guild to prepare for Flame .. something
here is a short film
[ame="http://www.youtube.com/watch?v=ZJFC5PZhHYE"]YouTube - Ulduar exploit[/ame]
Just to add.
All texture except the road to the left at the end of the movie is just 'air' which you will fall through, and die.
When following the road on the left, you'll end up at the front of Ulduar, and a dead end further in.