How important is White Balance(WB) anyway?

From Izzy Video Wiki

Setting the White Balance is usually very simple. There are usually several settings. My camera has manual(set with white piece of paper, more on this later), auto, indoor incandescent or halogen, or outdoor. Using a white piece of paper with the manual setting is by far the best option on my camera. I keep a white piece of paper in my camera bag for this purpose.

Just to give you an idea how much difference manually setting white balance can really make I have examples.

This first video(pardon my big toe there :) is with white balance set to auto in a small room with incandescent bulbs: Auto White Balance

This second video(again, pardon the toe) is after setting it manually with a white piece of paper: Manual White Balance