"Keeping your application up-to-date with the latest version of jQuery is always advisable, as it allows you to leverage the performance and API improvements the team is constantly making," said Adam Sontag, a member of the jQuery developer relations team.
Another improvement: The performance of event handlers -- such as a mouse click -- has been improved due to changes in the ".data()" method. The handling of hyphen-delimited data attributes has been modified to comply with the W3C standards.
Support for animations have also gotten a boost: jQuery now has a timer that can synchronize multiple animations on a single timing schedule. It also has support for the requestAnimationFrame specification in browsers where it is supported, which can help animations run more smoothly by alerting the browser when to repaint the palette for each animation frame.
The development team also added support for making relative changes to CSS (Cascading Style Sheet) values, made improvements to the Deferred object that can simplify more complex use cases, and more.
Now that jQuery 1.6 is finished, the development team is soliciting what changes users would like to see in version 1.7.