I'm also a JS
programmer, and about 4 months ago I started with a new company that uses jQuery for all it's AJAX communications. I hadn't really worked with AJAX much before this, I'm mainly a server side programmer.
I think you would really prefer letting jQuery do all of this fundamental AJAX processing for you, especially since their team of developers has worked out virtually all of the really nasty cross-browser stuff over the course of years. It frees you from learning all that stuff over the next several years before your program will work, and you can just focus on making your program do what you want it to do. The thing I really