Comment "Nav" controller confirmed semi-unnecessary (Score 3, Informative) 145
Reps from Zipper Interactive confirmed to me that the standard, Sixaxis controller can be used instead of the new "Nav" controller. The Nav replicates the left side of Sixaxis, anyway -- two shoulder buttons, one joystick, and simple gyroscope/motion sensing. Nav also has the face buttons, but so does the Move Wand, so those are a bit superfluous. If you want to save $30 on games that support the Nav, it's an option.