2.no change in the video input process, apple didn't add any kind of video resolution scaler so to input video from a non display-port device requires expensive adapters still.(pandering to MBP users again)
As I think you referenced, to Apple this option is really so the iMac can be used as an external display for other Macs. It would be nice, but HDCP is an issue. I could see it as a pretty good selling point for kids in dorms and bedrooms though. They could hook up their BD/PS3/XB into the iMac instead of a TV.
One thing I wish the iMac added was eSATA. Well, and a user upgradable SSD.