Technically, the canvas was released back in October. Honestly, all the updates seem more like "enhancements" rather than something fundamentally new: adding comments, co-programming, executing code within chatgpt (I don't think this is applicable for really large projects).
In general, we are waiting for the Day 5 update today. Let's hope they saved the most interesting for the end.
Video: https://www.youtube.com/watch?v=qZ0ImE41pVs
Documentation: https://help.openai.com/en/articles/9930697-what-is-the-canvas-feature-in-chatgpt-and-how-do-i-use-it
