Some people lately have been making a big deal out of using "X said" in dialogue, but like with a lot of writing do's and don't's, it is largely a matter of your individual style and the needs of the story. There's nothing wrong, for example, with having an exchange like:
"Don't be silly." Daniel said. "The moon is not yet right."
"He doesn't need the moon," she replied. "He has the ointment, and the skin-belt. I told you that."
Most of the time when people criticize the use of "said," (or, conversely, for not using "said," as when I used "replied" above) it has more to do with the repetitiveness of using "said" for every bit of dialogue (or, conversely, for never using said). Overuse looks something like this:
"Did you hear that howl?" he said.
"No," she said, "it's only the wind."
The thing is, if you look at some older works, a lot of dialogue has been formatted in different ways, depending on the author's needs and style. For example, some writers prefer something like a play format:
Daniel: The black moon howls.
Susan: Oh gods. Not you too.
Which, as the exchange grows long, might be abbreviated to:
D: I can feel it within me, crawling beneath this skin.
S: The ointment...you can't...not without something...
Actually, as long as you can readily identify who is speaking, you can sometimes dispense with names and "said" altogether.
"Cross my palm with wolfsbane," Daniel slurred drunkenly.
"You stupid bastard," Susan spat. "I should never have trusted you."
"Don't fight me, sweets." He said, smiling wide.
"My, what big teeth you have."
"All the better to eat you with..."
And of course you can mix and match, going back and forth between different methods. As long as it's legible and you can tell who is saying what, it's all a matter of your personal taste and preference. Personally, I often like to use a sort of intimation rather than "saids."
"Betteerrrr..." Daniel's teeth were outgrowing his jaw, long wagging tongue poking out between the sharp incisors.
"Good boy," Susan's voice was low and soothing. "Gooood boy."