1. A system for synchronizing output of audio content with textual content, the system comprising: one or more data stores that store textual content, audio content, and content synchronization information, wherein the content synchronization information corresponds to information for synchronizing the textual content and the audio content; an input device that obtains an input pointer referencing a location within the textual content; a display device that presents the textual content; an output device that outputs the audio content; and a processor in communication with the one or more data stores, the input device and the output device, the processor operative to: cause output of the audio content via the output device; cause presentation of the textual content on the display device; maintain, based at least in part on the synchronization information, synchronization between an output pointer of the textual content presented on the display device and an associated position of the audio content output via the output device, wherein the associated position of the audio content advances during output of the audio content, and wherein the output pointer indicates a position within the textual content corresponding to a current output position of the audio content; obtain, from the input device, the input pointer referencing the location within the textual content presented on the display device; during advancement of the output pointer, determine, independent of the obtained input pointer, a position of the output pointer corresponding to the current output position of the audio content; determine a lead interval based at least in part on a difference between the determined position of the output pointer and the location within the textual content referenced by the input pointer; and modify a speed at which the audio content is output via the output device based at least in part on the determined lead interval.
4. The system of claim 1 , wherein the input device comprises at least one of a touch screen, a mouse, a stylus, a remote control, a game controller, or a motion detector.