A couple of things here:
- Minimize and Maximize are still available and functional in the right-click menu and as shortcuts. Like always.
- When using GNOME Shell there’s only a Close button on the window, GNOME3’s default.
In one sentence: GNOME3 changed the default layout of window controls. Default being the important word:
- Can I revert this?
Yes, if you really want to. You only need to change a key in the configuration system. Just as you have always been able to change GNOME2’s window-controls configuration.
Please give GNOME Shell a try, don’t be afraid of changes. If it’s a bad decision, we’ll notice in time and fix it. It’s not the end of the world. Not yet 🙂