This is from the White House Blog;
"Here are the facts: The Constitution gives the President the authority to make temporary recess appointments to fill vacant positions when the Senate is in recess, a power all recent Presidents have exercised. The Senate has effectively been in recess for weeks, and is expected to remain in recess for weeks. In an overt attempt to prevent the President from exercising his authority during this period, Republican Senators insisted on using a gimmick called 'pro forma' sessions, which are sessions during which no Senate business is conducted and instead one or two Senators simply gavel in and out of session in a matter of seconds. But gimmicks do not override the President's constitutional authority to make appointments to keep the government running. Legal experts agree," he said. "In fact, the lawyers who advised President Bush on recess appointments wrote that the Senate cannot use sham 'pro forma' sessions to prevent the President from exercising a constitutional power,"
http://www.whitehouse.gov/blog/2012/01/04/americas-consumer-watchdog
According the HuffPo Obama rarely invokes his recess appointment authority, he has made 28 recess appointments. By contrast, former President George W. Bush made more than 170 during his presidency and former President Bill Clinton made almost 140. All because of the sham pro forma sessions.
So essentially a new precedent is being set.