I'm usually a pretty big stickler for grammar.  That's not to say my writing is perfect, or that the occasional error doesn't slip through, but in general it really bugs me when people can't write or communicate properly.

I capitalize and punctuate most of my text messages and IMs. Sometimes I'll let the caps fall by the wayside (except in the case of "I"), but I've always got my commas, periods, and yes - even semicolons and hyphens - in there.  Part of it is strictly habit, but the other part is communicating effectively.  It's the old "man-eating dog" vs. "man, eating dog" issue. I'm sure in context people can figure out what you're trying to say, but it makes a person look dumb when they use incorrect grammar.

An article I read (though I forget where) was trying to make the case for e-mails/texts/IMs that the sending party conveys a sense of importance and "busy-ness" by sending out crudely constructed messages, but I wholeheartedly disagree. I'm all about computers and quick communication, but I'm one of these people who feels proper grammar is essential to proper communication. 

If we start ignoring our rules of language, we won't be much better than a bunch of monkeys taking random stabs at the keyboard. *LOLROTFLMAOWTFBBQSCUBA!!!!!!1*

    -Tucker

I wholeheartedly agree with you.