I have been starting to use jQuery for a school project. I have done some javascript a few times. Form validation and stuff like that. I liked the syntax and loose typing but it is such a massive language and programming for the web is always a moving target.

Well jQuery does a good job of abstracting all the browser stuff away and once you get everything figured out it is pretty awesome. It is not really Ajax(although it has some Ajax handling) it is more of a merger of javascript and CSS. They also have an awesome plugin community.

The biggest problem I found was that the code is so minimalistic that it is sometimes hard to figure out what is doing what.