Something Positive had a great strip about one of the characters dumping his date on the spot when she said "lolled".
I don't understand the general intolerance for forum linguistic shortcuts. Every medium of communication has it's own vernacular. You don't talk on the phone the way you would have punched out a telegram in the '20s. I don't really see a difference between rofl, lol, omg, ftw, et al. and "Roger, Wilco" or "sincerely yours".
What I find abrasive is not the use of the internet lingo, it's the misuse. OMG doesn't bother me. OMGGGGGGG!!!!!!! is sort of annoying. "OmG wat u sayinng" is inexcusable not because of the "OMG" but because it's just sloppy. But on IM? You can bet I use "u" "wtf", etc. because it's appropriate there. You want to hit enter ASAP. I'm not retentive enough to review my IM's and my friends aren't retentive enough to mind.
American society was extremely leery about the introduction of the telephone into residences. There was a lot of talk about it destroying the community and such. I've read social theorists that suggest that it took about two decades for a social etiquette to be devised for making and receiving calls. The internet has been around for more than two decades, but forum culture is still a baby born in the late '90s. The etiquette is inarguably inchoate. We're making it up as we go along.
Edit: As pointed out by Valrus, who apparently is working pro bono as my editor.
