A new profile, 'nuke-default' has been added to the 0.7.1 config bundle.
http://sites.google.com/site/opencolorio/profiles

This profile emulates the 'out of the box' color processing luts that
come with nuke 6.1 (should you choose to use them).

I've also checked in the nuke script which is used to generate this
profile, which will allow for the generalized OCIO export of working
Nuke color configurations. This is exciting because for shops which
have configured custom Nuke color processing, you can export an OCIO
profile for use in other apps.

-- Jeremy