And Wii U is 53 on that yearly, which is a lot better than this time last year. Kinda surprised it's doing so well on Amazon.
The recent model of PS3 (CECH-4301C released I think only since january 2015 on Amazon) is sold at 30$ cheaper than previously. Same situation on bestbuy, the most recent model of PS3 is selling really well at 220$ instead of 250$.
There was an article last year on those newer models explaining the differences, probably in order to lower the production costs.
I think now we can safely assume an official 30$ price cut on all latest models of PS3s 500GB in US by Sony.
EDIT: I thought you were talking about PS3. Well, here is my explanation of the PS3 situation, dunno about Wii U...