Blogs: 'an audience of one'?

According to The New York Times, the sad truth is that more blogs fail each year than restaurants.

The article sited a survey conducted in 2008 by Technorati, a search engine for blogs. The survey found that only 7.4 million of the 133 million blogs the site tracks had been updated in the last 120 days. "That translates to 95 percent of blogs being essentially abandoned, left to lie fallow on the Web, where they become public remnants of a dream- or at least an ambition- unfulfilled," the article points out. Despite the fact that 7 million to 10 million active blogs exist online, one Technorati executive explained that "'it's probably between 50,000 and 100,000 blogs that are generating most of the page views.'"

Why do so many blogs fall by the wayside? The article explained that lack of reader interest, lack of time or preoccupation with other social networking outlets (Twitter, for example) can lead writers to neglect or even abandon their blogs. Others are disappointed when they realize that their blog is not the "fast path to financial independence" that it is expected- or hoped- to become.

Interestingly, some bloggers put their blogs on hold in order to regain- or protect- their personal space and privacy. This seems ironic, because blogs were once extolled for their their ability to 'democratize' the world of ideas.

What does this all mean? Are blogs here to stay, or does this survey indicate that blogs are a passing phase in the world of social networking? What are some ways to ensure the longevity of a blog? I have been interested in starting a blog, but my fear is that I would run out of ideas to discuss, or that I would fail to capture or hold readership. Whether you are a blogger yourself or a subscriber to others' blogs, I'd love to hear your ideas about what makes a successful blog and what you see as the warning signs of a doomed blog.