Nikon has released information on how to read their camera's white balance to third party software. Adobe says that ACR 3.2 (next version, not yet released) will provide "as shot" white balance support for the Nikon D2X, D2Hs, and D50.
Here is a link for Nikon's press release on the subject:
This may be nit picking, but it looks like Nikon and Adobe, only, has come to an agreement that both are happy with. Nikon is supplying a mini-SDK to Adobe. I don't think that is the same as making it public. I think Nikon can still choose to not supply this to someone they don't like.
Yes, I agree, I thought it was more open, but I don't think so now after I read the details. But it is still better than having to use NikonCapture.