We know Ajax is cool because we can do these nice auto-completing form fields and so on. Everyone tends to use Javascript libraries such as Prototype, JQuery or MooTools in order to get Ajax done smoothly.
For the last three weeks I’ve been working on creating a prototype of a Wordpress widget which retrieves search results from the WorldCat API and mashes that data up with information from other sources including (LibraryThing, Google Books, Amazon and Open Library).
Javascript libraries have become fundamental to good web design, almost all site nowadays have some element of javascript or Ajax present.
It is probably the main element in developing the Web 2.0 movement.
Google's search advertising is the best cash cow ever invented for the Internet. None of the well funded alternative search engine contenders are able to put a dent into that dominance.