The most common form of content in my area of interest is mainly occupied by tournament results. Obviously, my area of interest is related to sport, therefore the main content is results and tournament details.
The reason people follow tennis and certain web pages is to stay up to date with certain results and tournaments from around the globe. These results are fairly time-dependant and would lose interest over time, but this is the way the tennis industry works.
Another successful form of content is past players giving advice to junior players, like what is found in @jeffsalzenstein’s twitter feed that links to his personal website. The use of advice towards junior players is a common form of content because it is what a lot of parents and juniors are interested in, plus it’s a free way of learning how to play some of the more advanced shots in tennis.
But, overall the most common form of content is the results side of things, followed by technical advice and player blogs. It is fairly obvious why this is the case; individuals want to follow famous players results, and also strive to become a famous player, so this is why the most common form of content in my area is results and advice.