Except the Xbox 720 price cut was temporary, and sales are dropping like... cold cakes?
Link:
http://www.amazon.com/best-sellers-video-games/zgbs/videogames/ref=zg_bs_videogames_home_all?pf_rd_p=1286243362&pf_rd_s=center-4&pf_rd_t=2101&pf_rd_i=home&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=171Z2VYV011PDGVYWM1Q
It goes to show that sales will see a very temporary boost with new software and a price cut. So for less than a month Wii U could have higher sales, but they'll eventually drop to pretty much what they were before.