Comment 12 for bug 772177

This is the main reason I always disable desktop effects/compiz/unity.

When I'm working I alt+tab very quickly. Most of the times I don't even need to see the window switcher, I keep switching between the last 2 windows.

The problem is that the way it's done here not only you need to wait for the window switcher to appear, you also need to wait for the fancy selection to complete the slide animation in order to actually switch, otherwise it stays in the current window. So, in order to actually switch you need to wait 0.5 seconds, which I'm pretty sure I'm not the only one that is unable to tolerate it.

Gnome Shell has this fixed this btw, they don't wait for the animations to complete in order to switch windows.