Yeah, about 69 degrees. That was my ultimate setup on my 5in bike. Right now I am on about 67deg trail bike and it makes tech uphills more effortless as the front wheel is just waiting for a nod to pop off the ground, and the smooth uphills require only a slight weight shift forward. The real reward comes on fast downs.
"The difference between stupidity and genius is that genius has its limits."
-- Einstein, Albert