Hitwise tries to answer the question on why do blogs gain readership. in short, much of it comes down to subject matter and quality of posts.

Heather Hopkins took a look at three top blogs in various categories and tried to dissect the source of traffic. Particularly interesting is how those blog gains such amount of traffic, in some cases in a relatively short period of time.

• Girl with a One-Track Mind. Some of its blog posts appeared in the Sunday Times. The media frenzy surrounding the original author Abby Lee revealed her true identity as Zoe Margolis. The blog rocketed from a ranking of 133 in Hitwise’s Lifestyle - Blogs and Personal Websites category two weeks ago to 17th last week. The media storm contributed big ways to the increase in visits.
• Little Green Footballs. The blog came to fame after revealing that a Reuter photograph of Beirut had been doctored. The site jumped to a ranking of 26th the week ending 12th August 2006, up from 39th the week before. There was 88% increase in market share of UK visits week-on-week. Media contributed to the increase in popularity, but visits from blogs also grew to account for 14% of the site visits. Search engine become less important for the source of traffic for this blog.
• Arseblog. This site offers an example about how a blog has grown organically. People usually find the site generally through sport sites, particularly Football.

There are three points I think are interesting to sum it up:

1. Despite many blog evangelists boast that blog will replace mainstream media (MSM), it is not going to happen. The amount of work an MSM journalist do to churn out news content is nothing but hard work. In much cases, they spend far more time researching compared to bloggers. There are exceptions, but blogs are and will dominate the right end of the long tail of media sites.
2. Most blog sites are not going to be featured in mainstream media. Everytime we read about such news, there are marketers who advertise about how a blog could get you into the media. No, most blogs (currently 50 million) won’t. But there are ways to increase traffic organically, if you fill a niche that longs for what you have to offer.
3. There are still many benefits we can all gain from blogging. Most of them involve customer relationship management tasks. It is also about web publishing. Those matter to the business way beyond anything else.

Source: Hitwise.