I see the $149 price here under my iZotope account. It's about halfway down the page "Neutron 3 Advanced: Upgrade from Neutron 1-2 Advanced".

I haven't decided yet if I'll get it. I used Neutron 2 Advanced quite a bit when I first got it, but now I mostly just use the EQ module along with the Tonal Balance Control, often only the Tonal Balance Control.