Thanks for the replies. So, it appears that IMCR grandfathering has yet to be resolved, but the consensus is that holders will be granted some form of instrument flying privileges, for the whole of Europe, roughly equivalent to existing IMCR privileges.
With reference to your comment, Slopey, "But if a grandfathered IMCr was usable outside the UK, that would effectively make the EIR pointless", as I understand it the IMCR will no longer exist as of April 2012, so the EIR will become the only sub-IR entry route for instrument flying.
As the IR 'Lite' will be for IMCR holders only and should afford the same privileges as currently granted to IMCR holders (but across the whole of Europe), it seems to me that getting an IMCR before the April 2012 cut-off date would be a wise move.
Regards, jez