11. The method of claim 10 , further comprising: using the phonetic lexicon to perform recognition on the spoken utterance to generate a recognized transcript of the spoken utterance, said recognized transcript being characterized by a corresponding pronunciation; and generating an N-best list of alternatives to the recognized transcript, each alternative of that N-best list of alternatives having a corresponding pronunciation, wherein the initial pronunciation is selected from the N-best list of alternatives.
11. The method of claim 10 , further comprising: using the phonetic lexicon to perform recognition on the spoken utterance to generate a recognized transcript of the spoken utterance, said recognized transcript being characterized by a corresponding pronunciation; and generating an N-best list of alternatives to the recognized transcript, each alternative of that N-best list of alternatives having a corresponding pronunciation, wherein the initial pronunciation is selected from the N-best list of alternatives. 12. The method of claim 11 , wherein said recognized transcript has a score and wherein updating the lexicon involves first determining that the highest scoring pronunciation among the plurality of alternative pronunciations has a score that is higher than the score of the pronunciation for the recognized transcript and then adding the highest scoring pronunciation to the lexicon.