Many people in China call HTML5 'H5' and it had cause some heated discussion. Some people (developer) think H5 is non-professional, the other think it just a short name for HTML5.<p>How do you think of it?
Honestly, saying "H5" makes it sound like you don't know what you're talking about.<p>It's like calling HTML a programming language.
For some people it would be confusing with the current html tag <h5>. There's no name conflict in the case of JS (javascript). I think this is all about preferences. Human languages, as programming languages, are evolving. I don't see any problem with the case of calling html5 H5.
This names makes me think of an "old" social network that trended once Hi5[0].<p>[0] <a href="http://www.hi5.com" rel="nofollow">http://www.hi5.com</a>