Price details won't be revealed until after E3 2012.
Wii U will be out worldwide by the end of 2012, according to Nintendo's Satoru Iwata at Nintendo's end-of-the-year investor's meeting.
This is in line with Nintendo's previous comments that Wii U will be out before the end of 2012, which has been known for a while. This does confirm that it will hit every major region (North America, Japan, Europe, Australia) by the end of the year.
Iwata also commented that price details will not be announced until after E3 in June. Nintendo will host a press conference showing off Wii U the week following E3.