OK well I think I found my answer to the TOD question via this thread:
http://www.vehicross.info/forums/showthread.php?t=17667

So I take it the VX has an open front diff and a limited slip rear diff. The TOD system is basically a electronic center diff that direct's the torque to either the front or rear of the vehicle depending on drive shaft speed sensors detecting the slip.

Also from that thread answered my transfer case question, it's a center diff with electronic limited slip. But when put into 4wd low it locks the center diff to split torque 50/50 front and rear with no slip.

So in 4wd high the vehicle is basically like an AWD rear wheel drive biased vehicle.

Correct me if I'm wrong.

Thanks.