stocktonjc1110464 wrote an answer about Marmot 8000M Down Parka - Men's on February 8, 2012
Good point on the 850 vs. 800 fill power.
A rough, first-order, conversion between the two is possible, assuming full loft, etc., by simply multiplying the weight of 850 fill-power down by 1.0625 to arrive at an 'equivalent' weight of 800 fill-power. (850/800=1.0625).
Thus, the 13.6 oz of 850 down in the EB is 'equivalent' to about 14.5 oz of 800 fill-power down.
Also, I got some info on the new Mountain Hardwear Nilas Jacket (850 fill-power):
weight fill weight
22.25oz 7.6 oz (~8.1oz 800 fill-power equivalent)