when asked about spears todd said there werent going to be spears in the traditional sense, so people assumed he was thinking of polearms
Also, there was a diagram in a UK (i believe?) magazine that listed various combinations for the left hand and right hand. Both the horizontal and vertical axis' featured "Sword, Fire spell, Frost spell, Polearm, Shield". That's considered an official confirmation of polearms.
PS. The cell where two shields intersected was called "Confused turtle"
. And no, polearms weren't one-handed and they were included to illustrate that point (anything they intersected with was an X, meaning not possible).