I have the Dell 2405 LCD and highly recommend it for several reasons:
(1) It's $804 right now with coupons.
(2) The LCD panel itself is made by Samsung.
(3) The S-IPS panel used in the Apple display is touted to have better color accuracy, but reports with actual measurements indicate that the Samsung PVA panel in the Dell produces color very very accurately, more so than the Apple display.
(4) Dell service. 21 or 30 day return policy, no restocking fee, but you pay postage on returns. For exchanges, like if you get a bad display or one with some dead or stuck pixels, call Dell or use their online chat, and ask for a replacement to be sent overnight to you at no charge, and they will also include a pre-paid airbill for you to send the old LCD back. It sounds unbelievable, but one dead pixel is a valid reason for an exchange. Apple can't touch that, and their restocking fee is very hefty since the LCD is priced high.
(5) Inputs and adjustment options. DVI-D is useful for recently new computers, but I think the world is still using analog a lot too. Component video, S-video, and composite video may be useful now or later on for other things. Analog input is especially important because you can easily connect two computers to the display without buying a KVM switch (added expense and bulk or clutter), for example my PC and Mac mini are connected to the Dell via DVI and analog, respectively, and to switch between them I just press a button on the LCD. Also, analog KVM switches can be had for 15x cheaper than DVI KVM switches ($20 vs $300) and are more reliable/easy to get working.
(6) Adjustments. You can adjust color which may be important. But moreso is the ability to adjust how the image being displayed is scaled. I think on Apple LCDs, the image is scaled to fit the entire screen. That may work most of the time, but for things like iPhoto slideshows, OSX outputs a lower resolution than the native resolution of the LCD, and this is where you shouldn't scale the image because it'll look stretched and distorted. In other words, when viewing a photo at fullscreen on a 4:3 on a widescreen display, you want to see black bars on the sides to preserve the aspect ratio of the photo rather than stretching it to fit the screen. There seems to be no way to turn off scaling on the Apple LCDs.
(7) The two problems I've read about with the Dell is that there's a high-pitched buzz (but you can exchange it easily) and that brightness is too high (but you can turn down the brightness and colors to reduce to where it's pretty dim for those who like dim).
(8) Grainy-ness or glitter. Due to the nature of S-IPS panels, they have a slight sparkle, grainy, or glittery appearance. This is especially evident when viewing a white window and moving it around, so you can see that the grainy-ness stays in place. It's not too bad as I've seen on other displays, namely the Dell 2001FP, but it's there more than PVA/MVA panels.
(9) Swivel. I use the swivel on the Dell a lot. I think it's useful. I never rotate the display 90 degrees though.
(10) Built-in power supply. It doesn't require a separate power brick.
(11) Built-in flash memory card reader. I at first thought it was totally useless since I already had a cheap and convenient USB card reader that I use for SD flash memory, but I recently bought a Canon Rebel XT that uses compact flash cards. The card reader on the Dell display performs many times better than the other card reader for CF cards, so I've found a use for it.
The downsides of the Dell compared to the Apple are no firewire hub (I don't know how important that is, but I have a few iPods and use USB) and maybe less aesthetically appealing.