I thought this is an article that I must share.

It’s written by Collis from PSDTUTS, and you can find the article here.

It covers the following Topics:

1. Precedence (Guiding the Eye)

2. Spacing

3. Navigation

4. Design to Build

5. Typography

6. Usability

7. Alignment

8. Clarity (Sharpness)

9. Consistency

It’s also got links to some very good reference reading.
A must see in my opinion.

Cheers!