1. A method for labeling feature clusters in frames of image data for optical navigation, said method comprising: electronically capturing beacon light sources in said frames of image data as said feature clusters using an image sensor with an electronic imaging sensor array of an optical navigation system, said frames of image data including a current frame of image data and a previous frame of image data that are captured at different times; identifying current feature clusters in said current frame of image data; correlating said current feature clusters in said current frame of image data with previous feature clusters in said previous frame of image data based on distances between said current and previous feature clusters such that a current feature cluster in said current frame of image data and a previous feature cluster in said previous frame of image data that both correspond to the same beacon light source are correlated with each other; and labeling each of said current feature clusters with an identifier associated with one of said previous feature clusters that has been correlated with that current feature cluster, wherein at least one of said identifying, said correlating and said labeling is performed by a navigation engine in one of an integrated circuit and a processor of said optical navigation system.