The Power of IPS
Most of the computer monitors on sale this holiday season are, like those before them, based on what is called a TN panel. These display panels are known for being cheap to produce, and they can change color extremely quickly. However, they have extremely poor viewing angles and usually don't offer great color reproduction. They're adequate, but not great.
If you are looking to go a step above, you'll want to consider an IPS display. This technology greatly reduces the viewing angle issues common with LCD monitors and offers more accurate color reproduction. Movie and game buffs tends to like this because the depth and vividness of IPS displays is rarely found elsewhere, while image editing professionals demand IPS because they can work with an image as it truly appears, rather than an approximation.
There are some disadvantages to IPS, however. The most notable is price. Dell's Ultrasharp line, a well-known brand of IPS displays, starts at about $500 for the least expensive 24-inch IPS monitor. Other companies such as ASUS have entered the fray with their own IPS monitors, but you won't save much by choosing them. If you want a quality IPS display, you will have to spend a substantial chunk of change.
Another common problem is response times. When an action is taken on a computer, a certain amount of time is required for it to be reflected on a monitor. IPS displays are a little slower than TN panel displays, and the slowest IPS displays have been known to annoy gamers because of a perception of lag between their actions and what happens on the display. This is a product-by-product issue, however, and only hardcore action gamers would ever notice.