Satou: Thanks, the cheque is in the mail
The other posters said it correctly, you don't need advanced experience with JavaScript. You need average experience. To get to the next level of JavaScript you need to learn how to implement OO with JavaScript.
I learned OO with JavaScript many many moons ago using the book "JavaScript Objects" Wrox Press. I doubt it is for sale anymore, and if it was I would not buy it, unless it was used. The book is still up-to-date as I use it regularly, but I would cringe at having to pay full price for a tech book that is eight years old. Though I think Eric wrote something regarding Javascript? I think a valid question for Eric would be "Eric how much OO practices does your book cover and in relation to
Java Script Objects is it more or less?". Once you learn OO with JavaScript then writing Ajax code becomes very simple and straight-forward.
To your un-answered question:
Will Ajax be part of every Web project? Oh yeah! Will your applications only be Ajax? Not a chance! In another
thread where I talked about multiple device support Ajax is an arrow in your quiver. What I do think is that we will become used to developing UI's in different forms. Finally we will learn how to create UI's for disabled people, people that speak other languages, and devices that are large and small. For example, one topic that has not been discussed is; What about HDTV? Are your web pages HDTV ready? It's coming!