This is what facinates me.
In terms of the PS3 console itself... Why does it have three network ports on the back?
Because it can be a hub, rather than just being a terminal at the end of a network. Also, we want to be able to have a Gigabit port for an IP camera. So one of the ports is an in, and two of them are through. It can be a server as well as a terminal.
You showed demonstrations of the console running multiple applications across the two HDMI outputs - is that something which is actually built into the system's operating systems, or do games have to support it specifically?
Depending on the features that you exploit, some of it's handled by the OS, some of it will be handled by the applications. I should also explain that although yes, there are two HDMI outputs, you don't have to have only high-def devices attached to PlayStation 3 - there's also a standard PlayStation AV Multi-Out connector. So one of them could be an HD output, and one of them could be an AV Multi going to the TV.
Taking the demonstration of the video chat windows in one screen while a game was being played in another - is that something we can expect as a standard OS feature, independent of the game?
The Cell can run multiple operating systems, so yes, you could do that. Now, we don't have the application up and running yet, and the resource management isn't quite final - but the purpose of that presentation was to show what is possible. Exactly how that gets unlocked is still being worked on.