I've been composing a post about "Graphical Command Line" interfaces, which what alot of "AJAX" enabled features on websites are, and what Quicksilver, a Mac application, is... but it's getting so long and involved and I just don't have the time that I will give you a résumé of my thoughts on all this which I posted on Quicksilver's message board:
Quicksilver is a Graphical Command Line. It combines the ability to manipulate files and applications, executing application commands on files, like a CLI, while using the strong visual cues of a GUI, blurring the line between recall (CLI: gotta remember the right commands and where everything is) and recognition (GUI: navigate to where my files and apps are)...
When you use QS, you are constructing a command to execute, only you are not doing it alone in your mind (like in a CLI/Terminal/C Prompt) trying to remember everything, because as you type, QS *shows* you possible matches of what you may want or may do. The power of the CLI with the diminished need to learn "arcane commands"...
Other examples of GCL, meaning, where a predominantly text-input based User Interface guides you along with visual cues (even if they are text-based), are (in order of appearance in the ecosystem):
- Google Suggest / "LiveSearch"
- ecto & 1001's tagging mechanism
- Jonas's "tags4WP" WordPress tagging plugin
