Back at the beginning of March jQuery announced that the second beta release for jQuery 2.0 was available for developers to download and test out in their development environments. After looking over the release notes listed on the jQuery blog I found a few things very interesting for the next generation of jQuery.
jQuery 2.0 will not support Internet Explorer 6, 7, or 8, but will pass that responsibility over to jQuery 1.9, making jQuery 1.9 the best choice in my opinion for a couple of different reasons. Number one, Internet Explorer versions 6, 7, and 8 still carry a significant portion of the market between web surfers and corporate users making Internet Explorer always a necessary platform to consider when developing larger scale web application. Number two, the jQuery team made the API’s for 2.0 and 1.9 identical so that the 1.9 users are not missing anything that the 2.0 API offers. In short, if you are in a position to completely ignore IE, like a mobile app, then I would try out 2.0, but if you are developing for the rest of the web world, then I would stick with 1.9.
jQuery 2.0 along with Grunt allows you to customize a jQuery build of your own if needed. For example, instead of referencing the whole library, you can select only the core modules you need within the library and use the custom built version of jQuery this way. The advantage of using a custom build is of course, file size. In projects where load time and file size are a major concern, possibly in a mobile environment, using a custom build might be a way to conserve precious bandwidth.
To find out more on custom builds check out jQuery on GitHub Here