I'm one of those teachers who will respond to the word "mines" by asking "Gold or silver?" and the question "Can I go to the bathroom?" with "I don't know, can you?"
Yeah, you can say I'm a stickler about some things. It's genetic, I think. Just try ending a sentence with a preposition when my sister's around.
I'm critical about this because one of the things we teach in school (according to our curriculum, at least) is how to communicate well. People who speak "properly" are more likely to do well in interviews and score higher paying and/or better quality careers.
But it's not the only way people speak. I dare you to turn on a radio and count how many times the word "ain't" is used in one hour's worth of song lyrics. There, it's acceptable. In school, it's not.
It gets worse when you head online, where sentences like "LOL school is teh suxxorz I hav a gud job even wit low gradez." are easily understood and not criticized for grammar or spelling ... in some circles.
"In some circles" is apparently the key phrase here. In art we need to know our target audience, and we use our works, whether they're visual, auditory, or something else, to communicate something. I'm not likely to use Modernism to illustrate a children's story about a young boy's first week at school.
But online we have a wide variety of audiences with which we can participate, and the language norms can be incredibly different in each tab of our browser. Several people I follow on Plurk and Twitter are fans of some strangely talking cats, but you still won't see us posting things like "I can has Summer vacation!" or "Invisible budget" in our Professional Learning Networks.
So, if you remember how I started this post it's safe to say I'm not in favor of students handing in essays written in 1337 or LoLspeak, even though I'm capable of communicating in both. But I'm not so quick to dismiss these offshoots of the English language. They were created by a generation that found themselves understanding the new technology far better than most of their teachers, so they built their own rules around it.
And if you look at it that way, it kinda roxxorz.