I'd love to see an automated karma system that scored posts on correct grammar, spelling and readability. I guess that would discourage non-native speakers of a language from participating though.
I'm not saying that their ideas aren't worthwhile, but simply that the medium won't allow for those ideas to be presented in an engaging manner.
There's a huge difference between the wall-of-text full of typos and misspellings (which seem to become the weapon of choice of native speakers as well), and the misuse of pronouns, or forgetting which word is an irregular preterit. I, for one, would be in favour of seeing the former ranked lower.