the toshiba,panasonic,hitachi all use AIPS these panels have a good viewing angles but their contrast are at best 50% of what the sony and samsung .the best of AIPS panels produces around 1000:1 measured contrast compared to the sony models like 32,40,46 inch W series and 40,46 inch S,V series which produces a measured contrast of 2500:1(advertised as 3000:1) the new samsung models produce a contrast of 2340:1 they both are only beaten by the plasma like pioneer Kuro,panasonic ,pioneer the best has a contrast of 3500:1.
also the sony models produces the best black level of 0.10cd/m2 and samsung is a close second has a black level of 0.17cd/m2 while the best of toshiba are at distant last at 0.39cd/m2.
compared to pioneer plasma which produces a black level of 0.05cdm2 not far behind is sony's 0.10 cd/m2.