The summary of the NPRM says:
The Federal Aviation Administration proposes to amend the airworthiness standards applicable to transport category airplanes certificated for flight in icing conditions. The proposed standards would require a means to ensure timely activation of the airframe ice protection system. This proposed regulation is the result of information gathered from a review of icing accidents and incidents, and is intended to improve the level of safety for new airplane designs for operations in icing conditions. [Docket No. FAA–2007–27654; Notice No.07–07]Click here to download the entire document. (9-page 'pdf' file.)
The FAA is inviting comments from 'interested persons.' Comments must be submitted by July 25, 2007. The NPRM includes instructions for how and where to submit comments.