26. A computer-readable medium containing a program which executes the steps of: capture, via a microphone on a mobile device, audio data comprising a speech signal; inferring a context of a user of the mobile device; identifying a social graph based at least partly on the inferred context, the social graph comprising a list of potential speakers; and identifying a speaker determined to have vocally contributed to the speech signal, the speaker identification based at least partly on the identified social graph.
26. A computer-readable medium containing a program which executes the steps of: capture, via a microphone on a mobile device, audio data comprising a speech signal; inferring a context of a user of the mobile device; identifying a social graph based at least partly on the inferred context, the social graph comprising a list of potential speakers; and identifying a speaker determined to have vocally contributed to the speech signal, the speaker identification based at least partly on the identified social graph. 28. The computer-readable medium of claim 26 , wherein the program further executes the step of: storing a plurality of social graphs, each social graph being associated with a different context.