The 2012 RTDNA/Hofstra survey by my colleague, Bob Papper, shows that the number of TV stations mostly using or using some OMB (one-man bands) is nearly 70 percent. When Bob started the survey in 2008, it was just under 50 percent. He attributes this year’s increase to stations in the 26-50 market range (http://www.rtnda.org/media/three.pdf). Only 14 percent of TV stations do not utilize OMB in any way.
Here’s a link to a graph which charts the increase over the years: http://www-958.ibm.com/software/data/cognos/manyeyes/visualizations/new/stack-graph-for-categories/percentages-57/1