29. The method of claim 27, wherein the sequence of words in the user utterance comprises at least one word not present in the portion of the enrollment text.
27. A computer-implemented method for enrolling a user in a speech recognition system, comprising: obtaining data representing a user's speech from a recording device physically separate from the computer implementing the method, the speech including multiple user utterances and generally corresponding to an enrollment text; analyzing acoustic content of the obtained data corresponding to a user utterance to identify a sequence of words in the user utterance; determining, using the sequence of words, whether the user utterance matches a portion of the enrollment text; and if the user utterance matches a portion of the enrollment text, using the acoustic content of the user utterance to update acoustic models corresponding to the portion of the enrollment text, wherein determining whether the user utterance matches a portion of the enrollment text comprises a determination that the user utterance matches when the sequence of words in the user utterance is different than a sequence of words in the portion of the enrollment text.