HEFCE's consultation on proposals for the Research Excellence Framework ended in December 09. The Universities UK consultation response suggests that, though not addressed in the REF proposals, it would be beneficial if all REF outputs were made openly available. The full text of the UUK response is available from the UUK website. On open access, the document states "UUK supports the move toward ‘open access’ of research outputs and, although not mentioned in the consultation, would encourage the REF guidance to require that all submitted outputs are available through some form of open access mechanism. This would build on good research and information management practice. Work currently being undertaken by JISC and other stakeholders can support this process."
Of course, the White Rose Research Online system aims to hold research outputs beyond those to be submitted for the REF. Whatever HEFCE's response to the UUK suggestion, it's already possible for White Rose researchers to do what UUK recommends - at least, for a significant proportion of research outputs. And, as deposit into WRRO may well boost the impact of your research outputs, there's little to lose - but potentially much to gain - by depositing.