“We look at a lot of Ajax applications, and we have seen a lot of trends over the last couple of years. In general we are maturing, but as complexity has gone up in Ajax applications we are seeing one scary trend. The first set of apps simply added some <script> that did some happy XMLHttpRequest dancing. Then we abstracted to libraries such as Dojo and Prototype. Then people tried to do the right thing and use unobtrusive JavaScript where we keep the HTMl structure separate from the code. We would all like to see more of this. Unfortunately, we are starting to see Ajax applications that look more like Flash web pages…” (Thanks SuccessForce!)
btw, you can see some work XPLANE has been doing for Salesforce over at the Successforce blog.