Is this the white Nexus 4?
According to the EXIF data on the image, the picture was taken with an LG Optimus G last week. This may mean the image is coming from someone within LG, or it may not mean anything. It certainly looks like a white Nexus 4, and you can even see the reflective pattern on the bottom right that was a distinctive feature of the black Nexus 4.
We ran the image through FotoForensics, and it doesn't seem to be photoshopped, so it could be the real thing. Of course, this would only confirm the existence of the white Nexus 4. We still would have no idea when the device is planned for release.