Dieter Rams says good design is:
1. Innovative
2. Makes a product useful
3. Aesthetic
4. Helps us to understand a product
5. Unobtrusive
6. Honest
7. Durable
8. Consequent to the last detail
9. Concerned with the environment
10. As little design as possible
a good cheat sheet
from a man who knew
see also:
http://en.wikipedia.org/wiki/Dieter_Rams
http://upload.wikimedia.org/wikipedi...Principles.jpg