I like using that kind of stuff when talking to my health teacher because he has no clue what it means and it always gets us off topic. I told him about the Darwin Awards and we didn't have class for like 3 days, ROFL!
Sometimes I have no idea what they're saying [when its on the radio without translation]...I'm like when they came up with this......and you soooo know you bff rose before
I say TMI. And I've slipped up and said "pwned" before, which was mightily embarrassing and proof that I have reached critical nerdness. But otherwise no, I don't use any 'netspeak'.
Oh, I do say "nom nom nom" and some other lolcat stuff, but I only say that to the dogs.