001,
I thought you spotter boys had to see the aircraft for 'real' to log it in your book?
The main reason we would not be happy with ATC radar (delayed or not) on the net are mainly due to security reasons. There are plonkers out there who 'get off' on trying to push out hoax instructions to pilots. The less ammo we give them, the less chance of a disaster. While we respect your right to enjoy your hobby, some things are best left just as there are. The Wireless Telegraphy Act also comes into play here.
As for what the Yanks do on the Net is up to them, they of all people should be ultra sensitive to this information being freely available in light of 9/11