Which is better?

Apple 23"

The Apple 23" is advertised as an HD monitor. I'm not sure what the specs of the Dell are.

 

They are both HD monitors (it doesn't take much for a computer monitor to be HD).

a.) No one seems to complain about the quality on Apple's monitors, sometimes some whining on the price.
b.) There is occasional whining on the quality of Dell monitors, rarely on the price.

 

I wouldn't think either would be "better". The most important thing for photo editing is that you calibrate your monitor - not with your OS's built-in tools, but with a colorimeter. I use a Spyder 2 Pro, but there are other brands that probably work equally well.

FYI someone might tell you that "no LCD is as good as a CRT for color rendition"; but that's a recycled argument from around the time the dot-com bubble burst. CRT technology is certainly capable of displaying a wider color gamut; but the CRT displays sold by computer manufacturers (assuming you can find one anymore) aren't of that quality. You used to be able to buy rather expensive CRTs specifically for graphics work; but I don't know if they're sold much anymore. The few graphics pros I know all use LCDs. They tend to be Apple Cinema Displays; but most graphics pros are Apple fanboys anyway.