Web Technologies - AJAX

To date I am pretty outdated with what is going on in the web programming world where there are just a mixed of too many languages doing the same thing......same thing? Well, that was the wrong perception I have and reading up on AJAX gave me an insight of where the current direction of web technologies are heading.
The old world of web technology (web 1.0) I lived in was more about thin client - fat server approach where every change requires rendering a new page from the server. To improve on the features of websites, java applets or javascripts, was introduced that provided more work to be done on the client side (browser). All these technologies was to make the page feel more fancy and a better GUI. The current advance in web technology is to using the client-side script as a proxy that communicates with the server. This proxy will retrieve/send data from/to the server and minimize the effect of the change of data from the client's perspective i.e. client will not see a new page when only some data on the page needs to be changed. The objective is to make the page more like a desktop application - more responsive and smoother.
This all makes a lot of sense considering that there are huge computation power on the client's machine and that most of the time a web-page only need minor modifications to display a small change in data resulting from client activities. A great example is the popular Google maps where the page is pretty much the same except the maps change from user interaction.

If web service companies are to provide more diverse and powerful application services in the future, they will need more flexibilities and bridge the gap between desktop applications and web service applications. With Internet speed getting faster and faster, it is highly possible that server will only become a source of data and all the extra work done on the client side scripts.

I wonder if there will be a time when Internet is so fast and reliable that the browser will do nothing but redirect mouse activities and display images from the server. Thus the whole page is just an image that the server will understand. This is an extreme of thin-client and super fat-servers. This might be the way to go for mobile devices where the processing compatibility is limited. I don't think the responsiveness will ever be as good as client-side processing though.