Well, it's still a TN panel, the LED is just a backlight, instead of the traditional CCFL backlights. LEDs translate into longer lifespan (not that it really matters), "instant-on" rather than having to warm up the bulbs, and a brighter screen.
Most likely, it'll be brighter, resulting in more vivid colors and maybe better contrast. But google around, read some reviews and see what people are saying about it.