The 46Z4500's black levels are very good by normal LCD standards too. The shots of the Black Pearl when Elizabeth first discovers she's on a ghost ship suffer only very little with the customary LCD greyness, especially if you have the contrast booster set to medium and the backlight set right down to three or at most four. There's also enough shadow detail visible in dark scenes to avoid the ‘empty hole' phenomenon that can afflict dark picture segments in lesser screens.
If you're wondering why I went to the trouble of saying ‘normal LCD standards' back there, it's because we're starting to see a new breed of LCD TVs emerging that use LED array lighting rather than standard single fluorescent lamps. And these have already proved able to deliver black levels far beyond that possible even from Sony's 46Z4500.
However, given that we've found Sony's screen going for nearly £500 less than, say, the LED-sporting, 42in Philips 42PFL9803H, drawing too many comparisons between these two sets doesn't really seem entirely fair. So I'll cease and desist with immediate effect.
Some Sony TVs in the past have struggled a bit with standard definition sources. So I have to say I was worried that all the extra processing introduced with the 46Z4500 might really cause things to fall apart. But actually, while there's a slight tendency to exaggerate any MPEG processing noise that might be in a source, especially if you don't keep the contrast and brightness settings reined in, the 46Z4500 actually does a pretty capable job of upscaling standard definition sources to its Full HD pixel count.
Rather more unusual is the way the 46Z4500 can even emphasise MPEG noise in Blu-ray discs, especially in dark areas. Thankfully this problem can be considerably improved if you use the brightness-reducing Cinema mode, but please bear in mind that this mode actually reduces the brightness so much that it could be an issue if you've got a particularly bright room.