While checking about Lightroom 2.0 features and the new Adobe Camera Raw 4.5, I came to Adobe Camera Profiles. It is still in beta phase and the first public beta has just been released. It comes with DNG 1.2 and as far as I worked with this one, I believe this will take the color rendering of digital raw files to the next level.
I really enjoyed having my camera profile on ACR and being able to see my images just like my camera LCD. I think you should try it, if you already haven't.
Unfortunately, it does not show any profiles other than the camera detected from the exif, and not even the name of the camera (adobe says for certain reasons).
You need to use the dng profile editor to read the alternative manufacturer (say Cannon from a Nikon's user) profile from adobe camera profile beta as a base profile and save from dngprofileditor to create a new profile (in the case for Nikon). Then you could use this new profile (if you change nothing, that would be exactly the same as the Canon profile) in Adobe camera raw or light room.