If memory serves me right, in a VOA of Liqui-Moly's MoS2 Oil Additive, there was something like 4,092 PPM of Moly. That is way more than what you will find in a standard off the shelf oil.
Using it in different applications, I have found it not only smoothens out the operation of the engine, but also has a minor affect on oil consumption in a positive way. Those are the reasons I add it to my oil at every oil change, although I'm tempted to go with Cera Tec later on. Here's a video some may find interesting:
Originally Posted By: Liqui-Moly
The anti-friction lubricant MoS2 forms a high load-bearing film of lubricant on all friction and sliding surfaces. This product reduces friction and guarantees energy-conserving performance for the unit. This yields the following advantages: significant savings in fuel and oil consumption, scientifically proved reduction in wear, fewer break-downs, emergency lubrication properties. Tested on catalytic converters and turbochargers.
I don't know about it 'considerably reducing fuel consumption', but it certainly does have a slight affect.
I've always used Liqui-Moly lubricants in my Ford 4.6L, although I'm looking to try Mobil 1 0W-40 at the next oil change without any additives, just for the sake of experimentation.