According to Nielsen SoundScan’s mid-year report, album sales (CD + digital) have dropped 3.2% during the first six months of 2012 to 150.5 million units from 155.5 million a year ago. CD sales declined 15.1% in the second quarter of 2012 to 42.6 million units, compared to 51.4 million a year ago. Meanwhile, digital album sales have seen a jump of 13.8% to 57.2 million units in the first six months of 2012, from 50.3 million a year ago.
Without question, a large contribution of physical scans has come from Adele's "21," which has seen 9.5 million U.S. scans since its release in January of 2011 and coming off a second resurgence after a huge night at the Grammy Awards back in February. In fact, the #1 selling album of 2012 so far has been Adele's "21" with 3.67 million units.
As far as digital singles go, both Gotye's "Somebody That I Used to Know" and fun.'s "We Are Young" (featuring Janelle Monae) surpassed the 5 million mark with scans of 5.5 million and 5.1 milion units respectively.
More details available here (via Billboard.biz).