I love org-mode. I have never found an online todo-list or task manager that I like to use... but plain-text lists fit my mental model perfectly. org-mode is plain text on steroids... also the clocking abilities while doing tasks is incredible.
Just the other day I was thinking of a good web front, which can be made for org files which are in Dropbox or something. Then, when on a computer with emacs, those files can be edited via emacs and otherwise, via the web app. This would also help in bringing other non emacs people on the orgmode wagon.
I started doing a webapp like you talk about, since I needed to learn JavaScript. I call it Attorg, "atto org". I never planned on doing more than an absolutely minimal feature list, since people can use a terminal implementation in the browser (for e.g. Babel).
But I began a new job a month ago. The web side is at most half done for MVP. The server side is three pages of code (using said CPAN module).
My use case was a nicer and simple version for my iPad than the normal iPhone/iPad app. I never figured out how to do a nice menu system for commands, most of it is ~ normal key codes.
Since it is Emacs related, it will be the latest GPL, of course.
I'll try to get it up on GitHub or something this weekend. If you post an email in your profile I'll send you the address.
(Note what I wrote -- I'm a JavaScript beginner; the less than 40 pages of "Attorg" is ~ half of all JavaScript I've ever written! Also, it really need lots of loving from someone that has taste... [Edit: Both UI and UX.])
Disclaimer: This is so true... http://search.cpan.org/~sharyanto/Org-Parser-0.30/lib/Org/Pa...
Edit: Clarity.
If I can't get it done the next weekend I'll pack it up and email it to you. :-(
https://github.com/berntb/attorg/
The server Perl code doesn't do much except load an org file into the javascript side.
It needs Twitter Bootstrap + FontAwesome.
I'll update it to a working installation a coming weekend, must sleep now...