JISC has released Final Report: Usage Statistics Review.
Here's an excerpt:
The JISC Usage Statistics Review Project is aimed at formulating a fundamental scheme for repository log files and at proposing a standard for their aggregation to provide meaningful and comparable item-level usage statistics for electronic documents like e.g. research papers and scientific resources. . . .
The thus described usage events should be exchanged in the form of OpenURL Context Objects using OAI. Automated access (e.g. robots) should be tagged. . . .
With the JISC-funded Publisher and Institutional Repository Usage Statistics (PIRUS) and the DFG-funded Open-Access-Statistics there are two projects which will formulate standards for usage statistics and work on their implementation. To reach broad comparability national efforts should be bundled together. A central authority—which could for example be the Digital Repository Infrastructure Vision for European Research (DRIVER)—should aggregate the usage data. . . .
Policies on statistics should be formulated for the repository community as well as the publishing community. Information about statistics policies should be available on services like OpenDOAR and RoMEO.