1. A method of estimating power consumption of an electronic device, comprising: estimating a power consumption of a gate-level implementation of an electronic device design, including independently calculating for each of a plurality of implementation-invariant nodes of said design an incremental power dissipation associated with that node, wherein said estimating uses an implementation module to produce a back-annotation database; wherein each of said plurality of nodes are either inputs or outputs of a design block of said electronic device and are invariant between differing gate-level implementations of said design block; and wherein said estimating is performed by a processing device.