This excerpt taken from the VRTX 8-K filed May 11, 2009.
Future accounting change
In September 2006, the FASB issued Statement No. 157, Fair Value Measurements (FAS 157), which establishes a framework for measuring fair value in United States GAAP and expands disclosures about fair value measurements. FAS 157 came into effect as of January 1, 2008, except for certain non-financial assets, such as capital assets and goodwill, and non-financial liabilities, in which case it is applicable for fiscal years beginning after November 15, 2008. We currently are evaluating the effect of adopting the remaining provisions of this new standard.