Actually in the market both are same.
WLEDs are also LCD except for the backlighting.
If you look closer, the technicality is little bit different: WLED has LEDs evenly distributed throughout the back of the screen so it turn off individually to achieve true black whereas
Standard LCD screens have a CCFL on top and on bottom of the screen (anyone who has disassembled an LCD knows this), and these light the entire screen, which means there will be uneven light conditions at different parts of the screen, and a true black is impossible, because the CCFL's can't cause just certain parts of the screen to go completely dark.