Is there a way for Cmd+Tab to display all of the instances/windows of an app?
An excellent example is here:
Notice how it shows the available instances of that application? That's what I'm looking for.
Witch does exactly that, with a ton of configuration options. It can also use the default Cmd - Tab shortcut.
If you don't care about seeing the window thumbnails, ⌘ - ` (the key above the Tab key) switches between open instances of an app.