HTML(HyperText Markup Language) is NOT a programming language, nor will it ever be.
HTML is exactly what it says it is, a markup language. HTML takes (literally) a day (or less, depending on your pace of learning) to master.
To get onto this topic, I had a fun chat with a really stupid teacher.
I was at my younger cousin's school, hanging around, talking to people, when I walked into his Computer Technologies class (Read: Keyboarding) and spoke to the teacher, just bullshitting around.
"Yeah, I have some programming knowledge, but I'm more of a web developer." I say.
"Oh, really? I happen to know some things about programming myself, I'm pretty good at it." She replies.
"Cool, what platform do you use, and what language?" I ask.
"HTML, and Mozilla Firefox." She answers.
At this point, I go cross eyed. It takes a lot for me to get mad, but when people claim they know a lot about a subject, then prove that they don't, makes me mad.
Anyways, I proceeded to amaze her with my "godlike skillz" on the computer.
If anything you could say HTML is a scripting language, but that's pushing it quite a bit.