I never really noticed this until recently, but when you have multiple tabs open in Safari that share similar titles, Safari automatically selects the most relevant part of the title to display.

For example, if you were to open several articles from this site, the titles would be something like brandon martinez: blog – It Really Is the Simple Things or brandon martinez: blog – Safari’s Tab Titles. Safari will automatically remove the brandon martinez: blog - so that the tabs would read It Really Is the Simple Things and Safari’s Tab Titles.

However, I have noticed that it isn’t 100% accurate. Results such as martinez: blog -[article name] aren’t uncommon, but either way, it’s a cool concept.