I ate pickled jellyfish at a restaurant in San Francisco's Chinatown. It didn't taste like anything besides pickled; texture-wise, it was sort of like eating tough pieces of animal fat. Chewy and stringy, but it was cold. I found it inoffensive, but I can see why a lot of people would be turned off by it... although personally, I think we should be eating a lot more of it given the massive jellyfish booms that have been occurring.
Especially because of the massive overfishing of other seafood such as Salmon and Lobster