The LC-32D40U showed up today at CC, and they were just rolling it out onto the floor when I got there, so I had them unbox it and hook it up right away for me. Sadly it was not hooked up side-by-side with the Samsung 3251D, which met with great aesthetic approval from the future wife the other night when we stopped in.
I'm not a videophile so I'm afraid I can't pinpoint the reasons behind what I saw like you all can, nor do I know how to configure all the settings optimally right there on the spot. I played around a bit, but aimlessly (I'm such a novice, sigh). And while I can't do a fair comparison with the Samsung because their floor model of that one was clearly defective--the screen would noticeably dim when switching from a bright scene to a non-bright scene--when it was looking OK the colors seemed markedly more vivid than the new Sharp. I wouldn't have even known to look for the phenomenon mentioned above about detail within blacks in dark scenes, so I will have to go back and see if that makes a difference to my eyes.
The Sharp was also disserviced by being set up--temporarily of course since they had both just been unboxed--right next to its 45" big brother. I was shocked at how the menu system looked to be lifted straight from the 1983 film WarGames when compared to the neat, professional looking graphics of the menu on the Samsung and the 45" Sharp. That is very petty I grant you. As mentioned the backlight is adjustable, from 0 to 16. I believe there were 3 color temperature settings (Cool, Normal, Warm was it?), compared to 4 on the Samsung. Another thing I remember thinking was that the remote control did not seem as functional to me as the Samsung's...button sizes, placement, etc.
That is not a very technical reaction I'm afraid so I apologize for that. But I am truly a blank slate on this--I have no brand loyalties or biases. I've never purchased a TV before, the only one I have had was inherited from a deceased relative. I have to determine if the Sharp looks good enough and fits my needs or if I want to spend the couple hundred extra for the Samsung.