What is your favorite Javascript UI framework out there ?
plq: Depends on your requirements. JQuery is great if your goal is also to maintain a progressive experience that somewhat works without javascript.If you're after a feel closer to desktop apps, or a high level of interactivity, and also don't care much about users who don't sport a modern browser, I think the best library is Ext, both in terms of community size and widget features. But, qooxdoo would be a better choice among free alternatives, (i.e. Sproutcore and Cappuccino)In a nutshell: In case of Sproutcore, I don't think Sproutcore's widget set is great. As for Cappuccino, I'm not sure about running code over an "Objective-j" layer on top of javascript, which is slow enough. And, I'm not a mac guy at all.Qooxdoo has introduced some support for progressive pages as well, but it's nowhere near JQuery. I'm also maintaining a project called JsQt, that converts .ui files from Qt Designer to qooxdoo code. See http://to./3t6p to get a quick feeling of what works and what doesn't. So you also have a basic gui-designer support for qooxdoo as well.