Another thing to keep in mind is that come 2010, Dodge will have the only proven 3500-5500 series truck. Both Ford and GM will be facing the 2010 emission standards with brand new engine designs. Which would you gamble on, the new Duramax, the Scorpion, of the three year old 6. 7?
... and Furd will never use the Cummins in their light duty super duty because the engine bay is too small. They have a difficult time getting the V8 powerjoke as it is now. I don't believe furd is willing to re-tool to fit a longer engine.