I do realise that there's probably some server-side things going on when you've submitted, but you could do that at the very last form input, and once the button is pressed, magic appears. No loading, no progress bars.
If javascript is disabled, these buttons do not work. Always need a fallback plan.
I know this is a WIP, and it's awesome. Very green though. ;-)
And as always, measure your audience. Why waste time and money for the 0.01% of users without js?
Without saying "screen readers", as they're 90%+ JS enabled these days.
You're claiming, millions are filling in long web forms with their feature phone numpad keys?
Give me a break.
If my JS would load in half, my no-JS form might also load in half, what do we do now. Have a fallback where we accept the form in pieces?
As for people who have a "personal preference", well, they might as well have a personal preference to browse the web via telnet. It's their problem.
The requirement to use a full, working web browser to browse a web page is hardly extreme.
Re: personal preference - have you never heard the saying 'the customer is always right'? No business in its right mind would purposefully turn down money from a bunch of its customers just because they happen to have a personal preference which can easily be accommodated.
Note that a web browser without javascript support doesn't fail to be a 'working browser' just because you say so.
Note that I am not saying you must do this on your personal blog, or that Javascript isn't a very useful feature of today's modern browsers. Just that it's good engineering practice to be inclusive and to handle exceptions gracefully.