Then, why is everyone so hyped up about HDMI? Why is it replacing DVI if it's better?
HDMI is not taking over DVI on PC's. DVI has never been on TV's, because TV's don't use high resolutions and do not use high refresh rates. HDMI's advantage for TV's is HDMI also carries sound.
On PC's, we don't typically hook up our sound to monitors, we have separate speakers.
The only place on computers that HDMI is taking over is with laptops, and I believe that is because they are being built to interface with TV's rather than monitors.