wordpress 3.8.1 & MediaElement.js

Hello, I was told that WordPress 3.8.1 is using MediaElement.js as it’s default video player. Please let me know if I am wrong. I have some questions about this player. can any tell me what is the best video format for MediaElenment.js player? currently, I am prepare my video file by using video converter as the following:
1) MP4 (apple TV)
2) H264 compression
3) AAC for audio

are there other requirements for this player? so IE, Firefox, Opera, Safari, Chrome, iPhone, iPad and Andriod devices can play.:)

Thank you

https://ww.wp.xz.cn/plugins/media-element-html5-video-and-audio-player/