When I first got my macbook, I didn't know the trackpad was supposed to be like that. But after a little getting used to, it's actually pretty useful since I find myself using both hands on the trackpad; my left thumb in the bottom left corner to click, and the right fingers to move the cursor.
It's only unresponsive if you start your finger motion from the bottom area, which seems to be about the height of a finger tip. You'll notice that if you start at the top part of the trackpad and then drag your finger and move it around the bottom, that area will be responsive.