I am using Fedora 15 with Gnome 3. The window title bars have only a Close button as control button. If you want to add other buttons here is what you need to do.
1. Install Configuration Editor
You can skip to step 2 if you have Configuration Editor installed.
Press Super (Windows) key and type Add/Remove and open Add/Remove Software.
Search for gconf-editor and install it. You may need to wait a while if you are using Add/Remove Software for the first time.
2. Use Configuration Editor to change button layout
Launch Configuration Editor.
In the Configuration Editor navigate to desktop>gnome>shell>windows
Find button_layout and enter the following to add Minimize and Maximize buttons:
If you want Ubuntu-like control box, enter the following instead:
3. Restart Shell or re-login
The changes are not instant. You either need to restart Gnome shell using Alt+F2 > r > ENTER (as reader Elliot pointed out in the comments) or you need to log out and log back in to see the changes.
Hope this helps.