Yes, I generally try to use correct spelling and grammar on webforms and other things like that. My spelling sucks, so that's not always the case. If I'm playing a game like America's Army and need to issue orders or something, then I'll not worry about capitalization and I'll use the jargon. However, the second you see me using l337 is the day you have my full permission to hang me by the neck with a Jinx shirt.
My friend who will remain nameless (Chris) uses the word "pwned" like it's nothing. But the problem is, he says it in real life, and with the people I'm forced to live around it embarasses us. Me and my other friend Shane are constantly like "Chris, shut the hell up" when he starts talking like that. (Of course, Shane says "ownded" IRL too, and it's scary.)
We must stop the l337ers before it's too late. Can someone say Neuclear Holocaust? Wait, that'll kill us too. I've got it! We must destroy the Jinx factory and destroy Jagex! (No reason for destroying Jagex except that they've turned Runescape into Ruinedscape and they must die.)
w00t! All your oil are belong to U.S.