What would the web look like if Google suddenly disappeared?

The Earth would continue as usual for 8 minutes, and then...no, wait, that's the Sun disappearing.

I guess you'd first have to look at where Google's tentacles are all in, and what would fail or be taken by others or maybe do better solo. As for search engines, there's plenty to take the void with a few major players, but again how many of them are powered or use Google's data for their delivery. Then there's Youtube. Lots of other factors I'm sure as well.

As big as they are, the web would adjust. Now do a sudden disappearance of Microsoft and its products. There's a black hole that would take a bigger effort to fill, if for no other reason because of decades of built up dependencies.