I want to talk about some aspects of web design and usability. DOM / Ajax technologies are great in that they provide a super fast response to user action but if the user recognizes specific behavior, I believe they naturally come to expect other standard behaviors and so when something other than those expected standard behaviors occur, the user becomes less confidant that they can predict what will happen in response to their actions - this leads to reduced user interaction.
For example…

1. Any pages with tabbed sections in the content area should not refresh the page. This does not include tab styled primary navigation.
2. Buttons generally refresh the page but a button styled consistently can do both (refresh & AJAX behaviors.)
3. Traditional looking links should refresh the page unless in the specific section, all traditional looking links have the same AJAX based behavior and this is consistent across the entire site (Think Microsoft Office help pages.)

The source of my concern about design standards comes from my use of Yahoo!’s new Panama PPC campaign manager. It’s actually very slick though there are strange behaviors I noticed, for instance - a small tabbed section showing different graph representations of our campaign performance refreshed the page when I clicked a different tab - also, a traditional looking link (underlined blue text) which AJAX’ed a whole section unexpectedly. I guess I’m only talking about functionality/behavior being intuitive.

I suppose the important thing is consistency. Consistency in style as well as behavior. I just wanted to make a point to say that I think there will and should be some emerging standards for AJAX based behaviors as its use becomes more widespread. If standards develop for sites which use AJAX based behaviors, it will only help everyone in the long run since less people will feel like they are out of control while browsing the web.