The Center for Marketing Research at the University of Massachusetts Dartmouth has done one of the first proper studies of the Fortune 500’s adoption and usage of social media:
One of the best-known forms of social media blogging was measured and analysed. The report found that only 22% of the primary corporations listed on the 2009 Fortune 500 have a public-facing corporate blog and have actually posted in the past 12 months. This was an increase from the 18% who did the same in 2008.
However (and suprisingly) 35% of the same companies had Twitter account that had one or more postings within the past thirty days.