Some evidence has been discovered within the code of the initial macOS Sierra beta that suggests there may be some truth to the rumors that Apple is building a MacBook Pro with a built-in OLED touch bar and Touch ID support. As noted by French site Mac Generation, there are several mysterious 'kHIDUsage_LED' references in macOS, as well as mention of support for "biometric devices."
Code found in macOS Sierra hints at rumored OLED touch bar, Touch ID support