What is all the hype with HDMI and DVI???

[gorilla196635]

What is all the hype with HDMI and DVI???
My Mits doesn't have the capability on it so I haven't had any experieince with it..but
The way i understand it is that it is a single cable connection for audio and video. One of my questions is, Is that all digital?
If so is one to assume that the DAC's in his TV or AMP are better than in the source player? Also most people running HT use the AMP for audio so does that mean you have to get an AMP to support HDMI or DVI and run everything through your AMP first and then to your TV for video?
Assuming that is true, is it really better to do all of that video switching vs. a direct connection to your TV?
And what about 6 channel audio DVD-A and SACD.... Still need to connect those analog...
I will stop now because I have way too many assumptions going on here....
OMG this is insane........
Also people I have spoken to have seen no video improvement by using HDMI or DVI...

Thanks