I know that this is a popular subject, but I thought that I should ask anyway! Some think that it will be Gandi IDE, others think that it will be (removed by moderator - please don't encourage use of unmoderated sites), but I have no idea. I was asking what the most probable website was for 4.0.

What are you particularly asking? Please specify.

If you're asking about Scratch 4.0, no news has been released on it just yet, and that's probably in the distant future. We can expect Scratch 4.0 to be definitely an upgrade (technologically wise), but for now, Scratch 4.0 has not been officially confirmed, despite ongoing rumors.

There is not enough released information to have a discussion.