As almost anyone who works for a living knows, the Internet is fundamentally, and irreversibly, changing the way job seekers find employment — and employers fill jobs.

According to The Conference Board, in October 2006 there were 2.5 million new help wanted ads posted on job search sites or through online newspaper ads, up 28% from a year earlier.

"The Internet has made its mark on a range of human activities from shopping to dating to banking and investing," says Jeffrey Grau, eMarketer senior analyst and the author the new Career Planning and Job Hunting Online report. "It should be no surprise, then, that the Internet is also changing the way people build their professional lives."

In 2005, the Pew Internet & American Life Project asked adult Internet users whether in the past two years they had faced any of the nine major life events listed below and, if so, whether the Internet had helped them to deal with the issue. Career training was ranked as the fourth most common major life event (39%), but second in terms of the Internet’s role in helping people deal with the issue (39%). Changing jobs also appeared on this list of major life events, but respondents indicated that the Internet plays a less vital role in this area than it does in career training.

Visitor traffic volume is another way to measure the relative importance of career and job hunting Web sites vs. other Web categories. Hitwise, an online competitive intelligence service, captures unique visitor numbers and converts them into market shares. The 10 Web site categories shown below accounted for 16.7% of the visits to all Web sites in October 2006. "Employment and Training" Web sites were more popular than investment, religion and wedding Web sites, if somewhat less popular than shopping, government, health and dating sites.

The Conference Board’s top 10 list of occupations advertised online from January to September 2006 contains mostly white-collar jobs.

"It is no wonder that the preponderance of Internet job ads are for white-collar positions," says Mr. Grau.

According to comScore Networks, one in four (24%) visitors to career Web sites (including job hunting sites) have annual household incomes over $100,000 and over half (55%) have household incomes of at least $60,000.