The National Snow and Ice Data Center in Boulder, Colorado, has called it:
On March 18, 2012 Arctic sea ice likely reached its maximum extent for the year, at 15.24 million square kilometers (5.88 million square miles). The maximum extent was 614,000 square kilometers (237,000 square miles) below the 1979 to 2000 average of 15.86 million square kilometers (6.12 million square miles). The maximum occurred this year 12 days later than the 1979 to 2000 average date of March 6.
This year’s maximum ice extent was the ninth lowest in the satellite record, slightly higher than the 2008 maximum (15.24 million square kilometers or 5.88 million square miles) Last year, 2011, was the lowest maximum on record, 14.64 million square kilometers (5.65 million square miles). Including this year, the nine years from 2004 to 2012 are the nine lowest maximums in the satellite record.
Update: The NASA Earth Observatory website has an article about the maximum. I'm copying the following quote by Walt Meier:
On average, Arctic sea ice has historically peaked around March 6, but the maximum extent has tended to occur later in the month in recent years. The cause for the later peak is unknown, but NSIDC’s Walt Meier suspects it might be related to the minimum sea ice extents that occur each September.
“There are constraints on how long Arctic sea ice can keep growing in late March,” Meier says, citing springtime sunlight and rising temperatures. “But since Arctic sea ice has melted so much in the summers, it could be that the ice has more room to grow at the end of the season.”