Well this has been an incredible time for monitors. Basically after a long multi year period, it is getting interesting again. There are two pieces of news and some new recommendations from 4k.com and tomshardware.com
4K monitors
These are now affordable and wow, if you are doing spreadsheets, writing software or the next great American novel, they are a dream. A 27" really doesn't do it, but 40" really changes your life. The Philips BDM4065UC is a 40" monitor that is like a massive television, it is so big, you can fit four HD screens and it is very usable. It is about $780 on Amazon now Now that 4K TVs are just$1K, this might seem like alot, but monitors hold their color and so forth really, really well. the big tradeoff is that it only goes 60 Hertz and only the most massive GPX (the nVidia GTX 980 Ti) can even hope to drive it, but oooh, wait for the hardware to catch up.
The main problem with the monitor is the stand is just terrible. It isn't adjustable and the thing is really huge. The solution is to use the VESA 200 mount on the back (200mm x 200mm) and get the 8kg or 18 pound monitor up and off the desk with a swiveling arm. You first need a VESA 200 to VESA 100 adapter which is just a steel plate that fastens to the back. Most monitor arms are VESA 100 and designed for 27" monitors, but you just need to make sure you have something that adapts it and can handle 20 pounds or so. For $99, you can get an Amazon arm which sounds expensive, but the arm will last a life time. As an aside the premium is so low for a 4K monitor that you might as well get one, so an LG27MU67 is a 27" monitor with 4K, you can't really see it, but it sure is nice to not have an artificates. It is$470 or so at Amazon.
Gaming Monitors
The current state of the art is a 32" monitor (they really are cooler and bigger) than 27" that is a 2550p display running at 144 hertz to get smooth gaming. If you can get something that isn't a TN display that is awesome. There are two IPS panels at 2550x1440 that run neck and neck. The Acer XB270HU $700 at Amazon although the reviews there are not so hot. We have one and it is phenomenal. Very hard to go back to just 1080p again after using it. Color Accurate display This is for those cases where you are doing photography. First you have to color calibrate then you can get really nice WYSIWYG. The LG31MU97C-B seems perfect for that. It is$920 at Amazon but wow is it accurate.