Apple may launch an ultra-thin 15-inch MacBook laptop as early as the second quarter of 2012 according to a new report. Components for the new notebook have already begun shipping, DigiTimes reported on Tuesday, though details are extremely limited for the time being. The site’s nameless sources say that components started moving this month in small volumes, perhaps for test runs of the new computer. As was the case when earlier reports emerged regarding the new laptop, it is unclear if this new model will be added to the high end of Apple’s MacBook Air line or if it will simply be a new, thinner MacBook Pro. Mass shipments are currently scheduled to begin in March according to the report, though firm launch timing is unknown at this time.