This is not 100% HTML content it includes video/audio other media type content. I found based on html5 new tags, the size of the page can be reduce upto 50% of the total mark up size. What it means is using concise tags eliminate unnecessary markup like extra html tags and CSS and otherstuffs. And also two important media tags Video and Audio would reduce plugin code (it may be one time + some other extra stuffs) It would be huge boon to network. Websocket will enable easy push feature and binary data transfer which also will play friendly to payload. So ultimately new version html (html5) will need less mark up to achieve same effect and also some time less extra enabler code. Size reduction is mainly due to as I said above, Since reduction in html code to achieve same look and feel will ease the Search engine parsing -- it also saves power cost and hence environmental friendly --- connecting loose ends. One more side effect would be performance improvement on the browser as browser needs to parse, understand and apply style etc to only few elements.
- New html tags so less mark up
- New media tag - video and audio so less dependency need for using media
- Websocket -- duplex communication eliminates unnecessary round trip and concise data transfer
- Improved browser performance
- Search engine friendly -- less markup to parse and no proprietary plugin to understand
- Less power usage - markup generation and Search engine content parsing