The US National Science Foundation has posted some material on the new requirements for data management plans. In particular, see

Preparing Your Data Management and Sharing Plan - Funding at NSF | NSF - U.S. National Science Foundation

which includes a pointer to the overall Grant Proposal Guide language on data management plans, a pointer to the NSF data sharing policy, and some additional pointers to specific requirements for individual directorates and programs.

Clifford Lynch Director, CNI