Support for pushing (though not pulling) h264 files. If pushing to an HD
TiVo, the Push() function tests whether a file has h264 video and
mpeg4aac or ac3 audio; if so, it will (attempt to) send it without
transcoding it. This is limited right now, and can have false positives.
There's no testing of the container (must be MP4 AFAIK), nor that
"streaming" mode is set, for instance. If a push fails, it will not be
retried, but you can pull the file instead (in which case it will be
transcoded to MPEG-2).