we're talking, we're going to talk, we'll talk

[joham]

The following is what the host says in an interview, taken from one of China's senior middle school textbooks:

In this hour, we'll talk about what our life will be in the future. Let's warmly welcome Dr Smart, a professor from Future University! He'll tell us what he thinks about our future. Professor Smart, your many predictions made 30 years ago have mostly come true. People want to know more. There are many high school students here who are curious to know what new predictions you will make about the future.

From grammar books, I've learned to use "we're talking" or "we're going to talk" or "we'll be talking" if the talk is the result of a previous decision or arrangement. And the "will" used to talk about the future is preferred in formal written English.
Could you tell me why "will" is used in this spoken passage? The talk seems to be a previous arrangement, and it doesn't seem formal either.

Thank you very much.

[Tdol]

I think the key word in the text if 'prediction'. However, I wouldn't use 'will' the way they have. I would use it in his speech, but not in the introduction.