I recently published a screencast about jQuery on ShopHighOnCoding. The screencast is 38 minutes long (yup! it is long) and covers different aspects of the jQuery library including jQuery notation, effects, drag and drop, sorting and jQuery Ajax API. The screencast is available with a small price of $4.99 and trust me it is worth it. So, if you are interested in quickly understanding the power of jQuery library then check out the screencast using the link below:
Tour of jQuery Library