Usability methods are like sandpapering a chair. If you are making a chair, the sandpaper can make it smoother. But no amount of sandpaper will turn a chair into a table.
Keep it simple: In general, interfaces should use simple geometric forms, minimal contours, and a restricted color palette comprised primarily of less-saturated or neutral colors balanced with a few high contrast accent colors that emphasize important information. Typography should not vary widely in an interface.
To our human minds, computers behave less like rocks and trees than they do like humans, so we unconsciously treat them like people.... In other words, humans have special instincts that tell them how to behave around other sentient beings, and as soon as any object exhibits sufficient cognitive function, those instincts kick in and we react as though we were interacting with another sentient human being.
It has been said that the great scientific disciplines are examples of giants standing on the shoulders of other giants. It has also been said that the software industry is an example of midgets standing on the toes of other midgets.
Run for your lives-the computers are invading. Awesomely powerful computers tackling ever more important tasks with awkward, old-fashioned interfaces. As these machines leak into every corner of our lives, they will annoy us, infuriate us, and even kill a few of us. In turn, we will be tempted to kill our computers, but we won't dare because we are already utterly, irreversibly dependent on these hopeful monsters that make modern life possible.
Ironically, the thing that will likely make the least improvement in the ease of use of software-based products is new technology. There is little difference technically between a complicated, confusing program and a simple, fun, and powerful product.