For the most part, I agree that written-out laughter is often kind of lame. When I use it in my stories, it's usually to convey specific moments when laughter mixes with begging, or a coherent sentence suddenly breaks into a peal of giggles as the tickler strikes, et cetera. I'll kind of "hear" a particular verbal/laughing response in my head, and try to capture it that way. Outside of that, though, I tend to agree with the consensus about written-out laughter.
It doesn't kill the story for me or anything, though.