Originally Posted by
Stormcall
I don't abbreviate works to letters(so no "u" for "you" or "ur" for "your"), but acronyms do not bother me. "Brb" is fairly quicker than "be right back", especially if you're going back and forth so that you're having to say it with some frequency. Likewise, if something happens that you wanna get to quickly(your kid spills his drink, your dog decides that rather than letting you know he needs to go out, he's just gonna take a piss over on the washing machine) but don't wanna leave the other person hanging, "brb" is preferable to "be right back".
That said, I'd never use "brb" or "omg" or "wtf" or certainly not "lol" in regular spoken conversation. I do know people who do, though...