There's a lot of discussion these days around verbs of attribution. Elmore Leonard is an advocate of "said," and only "said." In an oft-quoted statement, he says, "The line of dialogue belongs to the character; the verb is the writer sticking his nose in." Novelist and founder of the Stanford Writing Program William Stegner agreed, saying that "said" was the least intrusive way to get across that the speaker had changed. "Said" is invisible, he said, absorbed by the reader, who moves on. Gasping, grumbling, cautioning, lying, and the like, all bring attention to the writer, and not to the story.
There's something to that idea of invisibility. You want your reader completely caught up in the story, not noticing the way you've put it together. The reader wants characters that are believable, plots that are exciting or surprising, descriptions that help paint mental pictures, not an abrupt detour into the writer's methodology.
But it's so boring, complain some of the writers I edit for. They get tired, they say, of writing "said" over and over. Think of it like "the," I say, or "of." You don't get tired of writing these words because they're useful. "Said" is the most useful of attributions in fiction. It makes your writing more seamless, more focused on the story.
And the dialog itself should carry the meaning. An actor should know to grumble or gasp from the plot, the character description, and the dialog.
Poetry is another genre and the use of more descriptive verbal attributes may well serve, but I am a proponet of good old, steady, invisible "said" for fiction.