The screencast is sans-sound, really just to try to keep my out-going bandwidth down, but I’ve commented along the way so you can understand (…hopefully…) what I’m doing, and why I’m doing it.
If you can’t view the screencast, try DivX Web Player for Windows or the Mac.
You can also have a look the code used in the screencast to have a play or to upgrade.
As always, let me know if you have any questions or suggestions.
Watch out for this gotcha that I just stumbled in to: if your form has an input element with the name 'action', the line
url: this.action is going to grab that element, rather than the form's action. Instead, use