You need to convert your LR3 photos to the new process version, PV2012. By default, any image developed in LR3 will remain on the older PV2010 process version. Until the process version is updated for a given photo, it will continue to use the old develop module sliders.
You should see a small icon with an exclamation point towards the bottoom-right corner of each photo. Click on it and you will see options for updating the process version.