What exactly you put into your title ultimately depends on what you decide is best — not what I personally think is best, not what John Gruber personally thinks is best. No one will know your site and your visitors better than you (assuming you’re a diligent publisher). Advice can be good, but advice from afar can also lack specific insight.
Most websites could improve their search engine rankings and traffic a fair bit just by improving their title tags across the site. Not only will a well-written title tag increase the chances of ranking well for a given keyword, but search engine users will be more likely to click through to your site too.
I haven’t seen a more thorough examination of what makes a good title tag than this article over at searchengineland.com. Well worth a read.