Black bags of Doritos chips wth the working title of “The Quest” have been on store shelves for several weeks now, and an online guessing game has been going on since their arrival. Interested in capturing the big prize? Entry deadline is Saturday.

Once again it seems the Frito-Lay marketing gurus have turned over the naming assignment for its new Doritos flavor to John and Jane Q. Public. (Remember Doritos X-13D?)

But is this contest really a flavor-naming game? It appears to be something more.

The contest is actually now in its final of four “puzzle release periods.” To have advanced to Puzzle Period 4, you must have successfully completed all puzzles released during Periods 1-3. To learn more about the mysterious game, you may visit SnackStrongProductions.com.

According to the contest rules, each of three finalists will receive a trip to a city within the U.S., where the finalists will compete in the Final Competition to determine who wins the Grand Prize in “jeweled treasure” valued at $100,000. (The winner may also choose 100 Grand in cash).

The Final Competition is described as “a series of events and stunts that will test the puzzle-solving ability and physical and mental stamina” of the finalists, and may include rigorous physical activities such as running, jumping, swimming, and/or climbing. If the Finalist is unable to partake in such activities, the rules state he/she may appoint a “designee.” (Is Michael Jordan available?)

Numerous posts from interested Web surfers have identified the new chip flavor as…Mountain Dew? Okay, that’s pretty obvious cross-pollenation between two PepsiCo products. And the new chips do taste rather lime-ish. We wonder: do they have the same caffeine jolt?

Anyway, stay tuned. We’ll try to publish the results of the Final Competition when it is completed in mid-July.