Some of the API changes can be found here: http://api.jquery.com/category/version/1.4/ http://api.jquery.com/category/version/1.4/ A full changelog, along with

Some of the API changes can be found here: http://api.jquery.com/category/version/1.4/ http://api.jquery.com/category/version/1.4/ A full changelog, along with information about the performance improvements, will be forthcoming.