Tom Hogarty has announced the availability of Lightroom 2.7 and Camera Raw 2.7. Along with a slew of new camera support, these new versions support the demosaic algorithm from Lightroom 3 Beta 2. Basically it will render the file as seen in Lightroom, but not allow you to make changes to the new Develop additions, like Grain, Process Version, the new Post Crop Vignette options, or new Noise Reduction. Because of the change you need to make a change to the noise reduction settings in Lightroom, to match 2.6.
(Via Lightroom Journal.)