I recieved my Dell U3011 yesterday but due to other things I haven't had a chance to connect it up until today. Just to note I got an A09 revision.
It's huge! That may sound obvious but it's true! I've only played a few games on it as I'm waiting until I have installed the OS on a new SSD before I settle in to things with the system.
I played Anno 2070 and previously at 1920x1200 you can see quite a bit, but needed to scroll around a lot. With this monster I see so much more at once! Those extra pixels with 2560x1600 really do help. Colours are superb after some tweaking (see blow).
Aside from gaming, using the monitor for office applications and multi-tasking is just the dogs danglies. How much additional space on excel?!! I thought 1920x1200 was excellent for having excel and vb open at the same time, but this just opens things up. It's akin to moving into a bigger house!
There were a few teething problems however. Hopefully talking about them here will help others.
1. When I first connected the screen, the display was bad. The text was all garbled like there were pixels missing and the colours slightly off. I thought it might have had something to do with my video cards in SLI or the monitor screwed from being transported. It was none of these; it was my existing DVI cable. This is the same cable I had been using on my 1920x1200 monitor perfectly fine; it just couldn't handle the extra resolution of the U3011. I used the one that came with the monitor and hey presto, nice clear text! Text size is perfect for me. It might be an illusion or placebo but it does look slightly smaller from my previous 24" monitor. Very much used to it now though.
2. The anti-glare coating is very aggressive. At first it looks like you need to give the screen a good clean, especially when you are working with a white background. Folk call it the screen door effect; looking at a picture as if through a mosquio net. You wouldn't want a white screen for a background wallpaper! I guess this is something that I'll get used to but some people just cant stand it. It's worth noting I don't thnk you'd notice it on any other background but white (or off-white) and certainly not while gaming.
3. The only other thing I'll add to what other people have said is to make sure after it's warmed for a bit is to adjust the brightness and contrast and load TFTCentral's custom ICC profile available on their website as a minimum setup. This is a good starting point to adjust it to your preference. I adjusted my bightness and contrast from 50 / 50 to 3 for the bightness and contrast still at 50 and preset mode to custom colour, just as they have at TFTCentral. With the ICC profile the display is just lovely.
Highly recommended if you need the desktop space, game immersion and have the cash available to spend.