I agree that many people's English (that includes me but I have a decnt excuse!) is poor. Misplaced apostrophe's (hehe), bad grammer, etc. Plus It looks messy when things aren't properly punctuated.
Regarding the use of colloqualisms - I feel that English is a living language and that local dialect is an important part of language today. English needs to change to stay alive - look at Latin. It died. Text message slang in Russia is very funny. When I was back there in the autumn it was strange to see the inventive use of that language(!)
Fidel