Hi Mouse,
I was being deliberately circumspect in my last post about the new ICC profile functionality in order to avoid possible discussions about copyright, but as Michael has suggested, it's now possible to use Nikon and Capture One profiles in RT, and (as a huge fan of Capture One colours - I've used that converter since r.3) I have to say that the use of the Cap One Canon 7D profile (or even better, something like the 5D Mk II profile, because the 7D profile isn't actually that good!) in RT is giving me images which are essentially indistinguishable from Cap One conversions, in colour terms - it's fantastic.
But the right place to discuss this, as the others suggest, is probably the RT forum.