Despite no mention at Apple's recent iPhone SE launch, a new 12-inch MacBook for 2016 is expected soon, after being spotted in Mac OS X.
It was inevitable that Apple would renew its MacBook for 2016 after it was released in March 2015. As March 2016 comes near to a close a reference to the new 12-inch MacBook has been reported by 9to5mac. The words: "12" MacBook (Early 2016)" were spotted in the Mac OS X Server application.
Previous reports suggested thinner 13-inch and 15-inch MacBook Air models would appear this year, perhaps branded just MacBook as Air replacements. This may still happen but there isn't a lot of evidence to support the claims.
After seeing the 12-inch MacBook (2016) mention in Apple's software, one intrepid user dug a little deeper in OS X 10.11.4 Frequency Vectors and claims to have found references to Intel's new Skylake processors in new MacBooks. Which new MacBooks these will appear in is unclear and with those rumours of thinner MacBook Air models for June, the new chip appearances may still be a while away.
The processors incoming are reported to be a 2.2GHz Intel Core m3-6Y30, 2.7GHz Intel Core m5-6Y54 and 3.10GHz Intel Core m7-6Y75.
When these will arrive is not clear but Apple writing "Early 2016" suggests we may see a MacBook refresh ahead of the WWDC event in June.