Just bought a new screen.
The Dell for IPS, input lag seems quite ok for gaming and I love the pivot-function. Some problems seem to occur with shiny edges of the picture, due to the orientation of the crystals of ips-panels.
If its available at your place, maybe you should look at the BenQ XL2410T. 24", 120Hz, LED, high contrast (needed for 3D), pivot and adjustable height. Stands right infront of me and I can not imagine a bigger viewing angle, being important to be a reason to buy an ips-panel. 160 degrees on the BenQ are a lot. Maybe this one is a bit pricy.
In German forums everyone loves the samsung BX2450 for beeing so affordable for its LED, 24" and nice picture.