The main drawback with Alt+Tab is it forces us to deal with more problems. For example, we want to switch to firefox task, the essential problem we're dealing with is finding the task using the clue "FIREFOX". After we press Alt+Tab, we get a window list in which all tasks are identified by icons. Now, we have to deal with another problem, finding out the icon that represents firefox. That's to say, our brain has to do a "context switch" from the "word processing" problem to an "image recognition" problem.
It's not intuitive at all. The idea of QuickSwitch is very similar to Spotlight on mac and FuzzyFinder on vim. We can keep concentrating on the "word processing" problem, no context switch.
QuickSwitch runs as a daemon. By using it, at any time we want to switch ao another task, press Ctrl+Alt+S key combination to bring up the QuickSwith main window, in which all tasks are listed. Then, type any part of the window title of the desired task and press enter to switch to it.
For instance, if we want to switch to firefox task. Type "firefox" in the input box. As we type, the window list is filtered. Those windows don't contain the word we typed in title are filtered out. When there is only one result left in the list, we can press enter key once to switch to it. If there are more than one one result left, we can continuing typing more characters to filter out more un-desired tasks. Or we can press enter to bring focus to the result list and use up, down keys (or Ctrl+P, Ctrl+N) to select desired task and press enter again to switch to it.
Source code:
http://code.google.com/p/quickswitch/
