The side panel for Gnome 2 is terrible. I use side panel exclusively when using Windows. I can't stand Gnome 2 one after using one that actually works properly.
With Gnome 3 it's possible to get a decent one through extensions or whatever. At least for my purposes it can be made to work correctly.
Although I find that using the 'alt-tab' or 'alt-~' to access window change dialog combined with arrow key navigation is superior to using the mouse in any situation. I know that lots of people are irritated by the change, but the way Gnome 3 is almost objectively better design.. it's most significant fault is that it's different then the Microsoft style.