Verizon changed their NE2 discounts this past February to $50 for plans over a certain price and $30 for lesser plans. The $100 NE2 is long gone.
I think you get the $100 NE2 credit if you have a smartphone. I have always had the $100 credit.
I went from a Palm Treo to my current phone BB Curve and have received a $100 and I just checked and will have a $100 credit for the HTC Droid Incredible.