Thomson Reuters has launched the Data Citation Index within the Web of Knowledge.
Here's an excerpt from the press release:
This new research resource from Thomson Reuters creates a single source of discovery for scientific, social sciences and arts and humanities information. It provides a single access point to discover foundational research within data repositories around the world in the broader context of peer-reviewed literature in journals, books, and conference proceedings already indexed in the Web of Knowledge. . . .
The Thomson Reuters Data Citation Index makes research within the digital universe discoverable, citable and viewable within the context of the output the data has informed. Thomson Reuters partnered with numerous data repositories worldwide to capture bibliographic records and cited references for digital research, facilitating visibility, author attribution, and ultimately the measurement of impact of this growing body of scholarship.