Industrial femtosecond laser delivering bursts of GHz fs-pulses are now available for a wide range of laser parameters (up to 100W in IR, 25 W in UV, 100 fs pulse duration, temporal shaping, etc.). An increasing number of laser applications are thus open to high efficiency femtosecond processing. The balance between ablation efficiency and processing quality is shown by systematic experiments we have performed on GHz femtosecond ablation of craters, lines and cavities for silicon, copper, aluminum and stainless steel. The burst duration/number of pulses in the burst is the key parameter of fs GHz processing, allowing a precise control of the thermal effects added on the known non thermal femtosecond ablation. As a consequence, laser processing based on thermal modification is achievable with the usual precision of fs pulses, such as welding of ceramics or of dissimilar materials or surface polishing. Recent work using GHz ultrafast laser also show promising and exciting perspectives in different fields such as X and Gamma rays inspection or quantum information.