I am not sure about the nuances in Mexico, but in the Spanish of the United States, which is largely derived from Mexican Spanish, chisme often tilts more toward the product of tattling than of gossiping. There are many periodicals called "The Tattler" in English, ever since Steele's famous "Tatler" of 1709, which has somewhat dignified the title and lifted it above the context of mere gossip. I don't know if this is of any use to you.

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Note added at 27 mins (2005-11-21 01:07:51 GMT)
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As for mitote, the Toltecs used it to mean chaos and disorder. There is another connotation in new age terminology. Not neessarily Mexican, but out there.

<<Say Yes! to becoming disillusioned. Do you want to continue living in your illusions? Do you want to be controlled, ruled by the collective illusions? Do you enjoy being stressed about money? Do you like having your stomach in knots when your partner 'cheats' on you? Do you feel fed by the patterns of your family insanity? Do you enjoy taking artificial medications? Do you enjoy the compulsions inside yourself that run you? Do you like the Illusion of the Government, the IRS, the MVD, your political system?

The Hindus call it 'Maya' or Illusion. The Toltecs call it the **'Mitote'**, or unconscious dream-fog.

If you're incarnated on earth you are most likely caught in the 'Maya Mitote'. Our minds, our egos, practically all our structures, social conventions, traditions, ways we're taught to behave etc. are designed to keep us caught in the web of the Illusion, the Maya, the Mitote.>>

From what I understand, you want to pick between "chisme" and "mitote" (not sure for what)

I give you the definitions found in the Diccionario del español usual en México:

chisme: [quite straightforward]
noticia o informe que se hace circular, bien sea verdadero o falso, sobre una persona que puede enemistarla con otra o confundir a quienes lo reciben: "Me contaron el chisme de que Pepe y Lucha se pelearon", "¿Sabes el último chisme?...¡Se divorcian!" "Corre el chisme de un golpe de estado".

mitote:
1. Fiesta muy alegre y ruidosa: ir al mitote, hacer unmitote
2. Reunión de personas en la que hay mucho alboroto, desorden y peleas: "La manifestación llegó al Zócalo, atacó la policía y se amró un gran mitote"
3. Ceremonia religiosa del ciclo agrícola, que realian desde la antigüedad varias culturas indias mexicanas, como los nahuas, los coras, tepehanes y huichoes, que se caracteriza por una danza .... para invocar a las deidades o alos santos que benefician la siembra, la cosecha, etc.

mito:
2. HIstoria, persona o cosa imaginaria o ficticia que se intenta hacer pasar por real o verdadera: "ESo de que era inteligente es un mito"

mitotero: is what you say of someone who just makes up stories and tells them as if they were true.