9. A system for synchronizing presentation of an item of audio content to a companion item of textual content, the system comprising: an electronic data store configured to store content synchronization information; and a computing device in communication with the electronic data store, the computing device being configured to: identify an uncertain region in the companion item of textual content, the uncertain region comprising text of the companion item of textual content for which corresponding audio in the item of audio content has not yet been identified; identify a region of the item of audio content that is preliminarily aligned to the text of the uncertain region; apply a language model including the text of the uncertain region to the region of the item of audio content to generate a textual transcription of the region of the item of audio content; convert at least a portion of the text of the uncertain region to a first phoneme string; convert at least a portion of the textual transcription to a second phoneme string; determine that the first phoneme string substantially corresponds to the second phoneme string; generate content synchronization information that facilitates the synchronous presentation of the portion of the text of the uncertain region in the companion item of textual content and a portion of the item of audio content corresponding to the portion of the textual transcription.
9. A system for synchronizing presentation of an item of audio content to a companion item of textual content, the system comprising: an electronic data store configured to store content synchronization information; and a computing device in communication with the electronic data store, the computing device being configured to: identify an uncertain region in the companion item of textual content, the uncertain region comprising text of the companion item of textual content for which corresponding audio in the item of audio content has not yet been identified; identify a region of the item of audio content that is preliminarily aligned to the text of the uncertain region; apply a language model including the text of the uncertain region to the region of the item of audio content to generate a textual transcription of the region of the item of audio content; convert at least a portion of the text of the uncertain region to a first phoneme string; convert at least a portion of the textual transcription to a second phoneme string; determine that the first phoneme string substantially corresponds to the second phoneme string; generate content synchronization information that facilitates the synchronous presentation of the portion of the text of the uncertain region in the companion item of textual content and a portion of the item of audio content corresponding to the portion of the textual transcription. 11. The system of claim 9 , wherein: the computing device is further configured to generate an acoustically confusable hypothesis for the first phoneme string; and the first phoneme string substantially corresponds to the second phoneme string if the acoustically confusable hypothesis for the first phoneme string is at least substantially similar to the second phoneme string.