Language is communication. It is used in one of three main ways:
1) Expression. If all you're doing is singing your magnificent Yawp to the world, have at it: it doesn't matter what conventions you follow or ignore, or even whether you speak in coherent syllables, as long as you don't care about someone else picking up on the communication.
2) Communication. This is where it gets tricky: you're trying to get the pictures in your brain to form similar pictures in my brain. In order to do that successfully, you absolutely need to follow all kinds of conventions. If you want me to imagine a pink curly-tailed animal wallowing in mud, you'd better not talk about the furry red duck Also, make sure you get your word order right: "Saw pink mud with curly I pig yesterday tail a the in" won't get you anywhere on the communication game. And if your audience doesn't speak English, a sentence like, "I saw a pink pig with a curly tail in the mud yesterday" will be a total failure at communication.
3) Aesthetic. Sometimes you want your audience to form pictures in their brain that aren't just similar to your brainpix, but that are beautiful to boot. Or, if not beautiful, then ominous, or hilarious, or impressive, or whatever. You want to convey something beyond the simple picture. In that case, you have a host of other conventions to follow. Are you trying to convey your hipness to an American teenager? Don't you dare say, "I looks as if I am winning this game, my friend." Instead, the proper expression would be something like, "Dude, I am so pwning your ass!" Conversely, if you're trying to convey to an audience of ENWorld posters that you've got linguistic chops, be sure to proofread your post and avoid the use of nonstandard English except in quotes or sly self-references.
That's my basic approach to language. Of course "pwned" is a word; by what strange and idiosyncratic definition of "word" is it not a word? It's a collection of morphemes that conveys a distinct meaning. Still, of course it is a word inappropriate to use in certain contexts. You should no more use "pwned" when writing an English paper than you should use "prolix" when chastising a chatty second grader during a math lesson (unless you're ready to take the time to divert your lesson into a vocabulary lesson).
If you're complaining about linguistic evolution through ignorance, I'm afraid, my childer, that you're going to have to go back a ways. The original plural of "child" was "childer," of course. Eventually people began interpreting that word as singular, and they began pluralizing "childer" as "children." That, too, has become an irregular plural, and occasionally people will pluralize "children" as "childrens." Thus linguistic change. At what point should we stop the bus?
Comparisons of linguistic defiance to defiance of the law ignore a fundamental difference between the two: the law is created by a central governing body, which spells out explicit penalties for defiance and backs up these penalties with force. Language is created by six billion people every day, with no central governing body, no explicit penalties for defiance*, and no force to back them up. Nobody ever got arrested for saying "ain't."
Language is alive; it cannot die as long as two humans are alive. People who speak a language cannot show it disrespect, except by trying to mummify it and preserve it in a museum. In its volatile, polymorphous, protean nature is one its most awesome strengths.
Daniel
* Some countries try to have these, so maybe I should limit myself to the US.
.
