On the Mac, yes. On Windows, no. Our DivX for Mac software is a QuickTime codec, so it will currently use the DivX Player or the QuickTime Player to playback DivX videos. On Windows the DivX Decoder supports Video For Windows (VFW) and DirectShow interfaces, but QuickTime does not support these interfaces.
Note that secure video downloaded as an online rental or purchase require the DivX Player for playback.