Treyarch’s Studio Design Director, David Vonderhaar, has stated on Twitter that Scorestreaks in Call of Duty: Black Ops 3 will reset upon death.
@PrivateCook1 Currently Scorestreaks reset on death; Specialist weapons/abilities do not. Pre-pre Alpha tuning but likely to stay that way.
— David Vonderhaar (@DavidVonderhaar) April 28, 2015
He also also confirmed that the abilities meter for Specialist characters are not going to reset on death; Vahn does note again that the title is in pre-pre alpha, so this may change before launch.