When you first installed LR4 and opened an image from LR to PS, you should have gotten a warning about needing Camera Raw 7 and it gave you three options; Cancel, Render using Lightroom and Open Anyway, it also had the option to Don't Show Again. If you clicked on that option, and used anything other than Render using Lightroom you'll have issues of the image not matching in Photoshop. In Lightroom you'll need to go to the LR Preferences and in the General tab, select the Reset all warning dialogs button. This will give you the wrning the next time you open a raw image to Photoshop. Then select the Render in Lightroom option. If you then don't want to see the warning you can select the do not show again option and from then on, Lightroom will simply render the file, save the file and send it to Photoshop.
