Do you know of a bleeding-edge HTML5 leveraging, legacy-ignoring JavaScript framework?
ajax, extjs, html, javascript, jquery
Solution
I am really having a hard time reconciling this idea after a serious thought. Assuming such a framework exists, it would only be as good as the current implementation status in any one browser. Let's say there are only two browsers and the HTML5 implementation status looks like this:
Browser | Feature X | Feature Y
-------------------------------
A | ✔ | ✘
B | ✘ | ✔
Then your most bleeding-edge HTML5 application can either have X or Y, but not both. If the features your application needs are available on the latest versions of most major browsers, then that feature is not bleeding-edge. It would have been bleeding-edge a year ago.
So depending on the project scope and goals, the most B-E application that can be written will conform to a single browser (the one that offers all/most of the features needed for your application).
If you're writing for a lone browser and do not want to fix any implementations deviations from the spec (as the spec is not yet finalized), then it's basically writing code for that chosen browser regardless of any specs.
If that is the case, then a framework is basically extra baggage to carry around. Instead, shortcuts for most commonly used APIs and other general simplifications would be the best way to go.
That said, if you're goal is to have a framework that vastly simplifies the HTML5 APIs oblivious of where the browsers stand today, then I would love to contribute towards that project.
Problem
What's the best framework (sort of jquery, extjs, etc like) to use if I'd like to intensively use all the freshest technologies of the HTML5 stack provided by modern browsers (Firefox 7, Safari 5, Chrome 14) and have absolutely no need to support any legacy browsers (incl. no need in IE support at all and no need in Firefox or Chrome prior to the latest stable releases)? I'd like to get all the newest available goodness without having (even abstracted by a library layer) a line of code meant just fore legacy compatibility or keeping any legacy-induced things in mind. To soften the filter, taking very humble hope of such an ideally fresh framework to exist, the least (the maximum level of legacy support) I'd like to agree is not supporting IE versions older than IE8, or better just not supporting IE at all.