Well, since I have been pretty dead on with my furlough 2008 predictions so far...
I don't think a combined Delta/Northwest will furlough anyone. I think the shear size of the carrier will enormously improve their pricing power, allowing the combined Delta/Northwest to raise fares instead of parking airplanes.
Honestly, I think Delta or Northwest has a much higher chance of furloughing IF they DO NOT merge. Having 6 legacy carriers in cut throat competition with oil at $112/barrel is a much scarier picture for furloughs.