At the end of my chat with Emmerich, I asked him about the status of Independence Day 2. Here's what he said:
"I came up, with Dean Devlin, with a story which we really liked. We ran it by Will [Smith], he liked it and we went to Fox and they liked it. And now it’s only like, 'Will there be a deal possible?' That’s all it’s down to now. But I would love to do it."
Ok, it's not much, but at least it indicates things are moving forward with ID4:2 or whatever they end up calling it.