[Liveblog - liveblogging may continue depending on batteries and wrists ;)]

Jeremy Keith is running through 'am I AJAX or not'. Good points about the definition of AJAX - it's such an abused term; people tend to equate it directly with 'Web 2.0' (another abused term!).

I guess ultimately from the point of view of the user, they simply don't care. It's not about whether something is AJAX or not, so much as 'does it work'; and AJAX techniques (used for good and not evil) can create that sensation. Users can get small bits of information back quickly without waiting - people like the feeling of speed and the page hasn't triggered boredom responses.

Jeremy goes on to suggest that the way to choose when to use AJAX is to get into pattern recognition - what user behaviour and expectation will benefit from AJAX? For example adding a product to an online shopping cart - the user doesn't want the whole page to go away and reload just because they added something to the cart. When you don't need to update the entire page, then it's a good time to use AJAX.

But, a bad time to use AJAX might be to have entire pages of search results - you're keeping less than you're changing. Traditional paradigms hold true and the user's experience isn't disrupted.

A great way to illustrate the principle of 'keep the user informed': Jeremy (like me, as it happens) likes the window seat on planes so he knows when the plane is about to actually land. The moment of impact is scary if you can't prepare, but really not too bad when you know it's about to happen.

Jeremy echoes somehing that Derek discussed yesterday in the Accessibility 2.0 workshop: if you emulate an interface feature, you must emulate it completely. Which is a great argument to support being a bit more choosey about when to use certain UI features. Do you really need to have drag and drop in a web app? Will your users expect it? Have you emulated every possible outcome of the drag/drop motion? You need to be aware of all the implications of what you're doing.

A big reminder: if it's not accessible, it's still no good! Things must still be accessible and usable. You don't get to dodge the accessibility requirements just because AJAX is 'new and shiny'. The good news is that AJAX does not preclude accessibility, but you have to be really aware of what you're doing and what will happen in screen readers.

In closing, Jeremy once again quoted Tim Berners-Lee: The power of the web is in its universality... In my opinion, I don't care if it is cliched to use that quote. For me it never gets old. It is and will remain an incredibly important statement about what the web should be.

I think it's a great thing for our industry that a talk on AJAX finished with a discussion of accessibility.