This is for my personal use.

Looking for a monitor to replace my aging ViewSonic, and that will go nicely with my new nVidia 590
Also, would be nice if my XBox 360 could go through it too (HDMI connection preferred).

26" or higher (will consider 24")
Low response time
Uses - normal, gaming, XBox 360.
Price - nothing too ridiculous.
Would be a nice bonus if it supported 2560×1600 resolution.

I have been doing some research, but I don't seem to be able to home-in on a monitor I like.