by: Roger Yu | USA TODAY

With the emergence of social media, more companies are replacing blogs with nimbler tools requiring less time and resources, such as Facebook, Tumblr and Twitter.

A survey released earlier this year by the University of Massachusetts Dartmouth says the percentage of companies that maintain blogs fell to 37% in 2011 from 50% in 2010, based on its survey of 500 fast-growing companies listed by Inc. magazine. Only 23% of Fortune 500 companies maintained a blog in 2011, flat from a year ago after rising for several years.