Hackers, Spelling, and Grammar?
"Correct english" is defined by one's environment of use, I believe. If in your environment, it is correct to say/write/type "should of" instead of "should have," then you will do so when communicating with English speakers of other environments. E.g., some Brits say "but-ah" when refering to what some USA-ians call "bud-er" and some Aussies will demand is "bud-ah" (you know, dairy product, usually yellowish, spread on toast, etc.). Extrapolate this to other languages, and, voila, you have one definition of dialects.
(Insert comment about global society here.)
Back to the question at hand, people spell the way they do and use the grammar they use because, in their most common linguistic environment, that is accepted, common, and expected. If a Texan spoke/wrote to a Minesotan (in his usual method of speech/writing), then the Minesotan would have to adjust his 'language-deciphering-skills' to account for the differences.
In summary, I believe that it is O.K. and even expected for new dialects to emerge and older ones to have difficulties when they come in contact. I believe that is the natural course of language.
However, IANAL. :)