This week, the FTC also released some new guidelines, the first changes it has made to its green marketing guidelines since 1998.

FORBES: Gang Green: Rules Are Tightening. Don't Say Green If You Don't Mean Green.

Given that, the renewed FTC attention to green marketing guidelines is probably a good idea.

FORBES: The Need for a Green Index

Companies including Safeway Inc. and Costco Wholesale Corp. are putting in place new guidelines to simplify fish-buying for consumers, and to promote their "green" credentials.

WSJ: Guidelines for Eating Sustainable Seafood

Specific guidelines of how to correct for the optimism bias in appraisals were published in the British government's Green Book, which provides an overall methodology for economic assessment.

CNN: Why we fool ourselves into optimism