Monitors are often viewed at close range, so viewing angles matter. As you know, the closer you're to the panel, the greater the shift. The new e-IPS and H-IPS monitors only suffer from extremely minor gamma shift. It also provides more consistent image, which is easier on the eye especially when viewing web pages with lower tone color (e.g. gray background with white text).
IPS panels also retain shadow detail and yield the most accurate grayscale and color, which is why they are used by professionals.
But if you need an LCD panel with deep blacks for movies and gaming, but willing to tolerate gamma and color shift, then opt for the c-PVA from Samsung. It is about the same price as the Dell.