- The length of your title
- Word proximity
- Keyword location
- Word order
- Repitition of words
- Titles for human consumption
- What words to use
The author contradicts himself a little - in point 3 he suggests better results from placing your keywords at the beginning of the title and then in point 6 reminds us that the Title tag is important for human consumption too. Ever looked though your browser's History and tried to find a site you were at yesterday and they have used keywords (or something else just as unpredictable) at the start of the title tag?
Like everything else, a balance is required.