There have also been reports of rising blacks on 2006 and 2007 models as well.
Thank you for your e-mail. Please be advised that we have not had any reports of black levels increasing on our 2008 models. We recommend that you do a hard reset of your TV, which will put the picture settings back to the factory defaults. To do a hard reset on your TV: turn the TV on, press and hold both the Volume Down on the front of the TV (not the remote) and Menu on the remote - simultaneously - until you see Self Check on your TV display. If you do not see Self Check then let go of the buttons and try it again. The TV is not reset until Self Check is displayed. Once displayed, unplug the power, plug it back, do the One-Time Set-up again.