I hope Infuse soon adds support for displaying italics from subtitles embedded in MP4 containers. Currently, the only way to get Infuse to display italics is to use an MKV container and/or an external SRT subtitles file.
It’s quite noticeable when watching sci-fi that has ships, since ship names are supposed to be italicized; for example, “Star Trek” subtitles saying “Enterprise” or “Battlestar Galactica” subtitles saying “Colonial One”.