Very brief overview of what AJAX is and what frameworks offer in general.
Discuss 3 different available open-source AJAX frameworks and libraries, and the perceived strengths and weaknesses of each. (Will show a demo screen from each framework):

Yahoo User Interface Library (YUI)

Strengths:
Very flexible; wide variety of controls and effects available
Extremely well-documented & supported; lots of examples available
Large user base, including many large sites
Huge developer community; YAHOO is very involved

Weaknesses:
Code-heavy (lots of required files = code bloat)
Namespace structure can make for overly verbose code (a necessary evil of the YUI)

script.aculo.us & Prototype

Strengths:
Lightweight, tight code
Excellent Ruby on Rails integration (ships with it)
Better support for the traditional object-oriented programming model (OOP)

Weaknesses:
Serious lack of proper documentation and examples
Small set of core effects and controls

Ext JS

Strengths:
Well-documented & well-supported
Fantastic, flashy UI for user controls; works nicely cross-browser
Very well-suited to an administration interface
Large user base, including some heavy-hitters (CNN, Adobe, Sony, Canon)

Weaknesses:
Relatively new framework; criticized as “just a widget library with a catchy UI” — lacking in other AJAX functionality
Commercial license required in for-profit use; open-source license for non-profit use

Briefly list some other open-source frameworks: MooTools, Dojo Tookit

Briefly list large-vendor backed frameworks: Microsoft ASP.NET AJAX (formerly “Atlas”), Adobe SPRY Framework for AJAX (HTML/CSS/JS centric, designer-oriented), Google Web Toolkit

Choosing a framework:
Highly-coupled frameworks integrate very well with your server architecture, but by default will tie you to a specific platform (e.g. ASP.NET AJAX, GWT)
Loosely coupled frameworks require more front-end JavaScript, but allow for portability of code, and less dependence on server-side technology (e.g. YUI, script.aculo.us)

Common pitfalls:
“Grass is greener” syndrome: switching frameworks mid-stream can be a major time and cost penalty
Avoiding the temptation to mix and match AJAX frameworks: leads to code bloat and the potential for conflicting JavaScript libraries

On-Air RELATED WEBSITE LINKS

Comparing Open-Source AJAX Frameworks (related blog post)
http://www.nickbouton.com/archives/2007/12/11/comparing-open-source-ajax...

The Yahoo! User Interface Library
http://developer.yahoo.com/yui/

script.aculo.us & Prototype
http://script.aculo.us/

Ext.js
http://extjs.com/

MooTools
http://moofx.mad4milk.net/

Dojo Tookit
http://dojotoolkit.org/

Microsoft ASP.NET AJAX
http://ajax.asp.net/

Adobe SPRY Framework for AJAX
http://labs.adobe.com/technologies/spry/

Google Web Toolkit
http://code.google.com/webtoolkit/

Show Notes RELATED WEBSITE LINKS

Comparing Open-Source AJAX Frameworks (related blog post)
http://www.nickbouton.com/archives/2007/12/11/comparing-open-source-ajax...

Protagonize
http://www.protagonize.com

Protagonize is a creative writing community dedicated to the (nearly) lost art of the addventure, a type of collaborative interactive fiction. One author writes a story, and others post branches to it in different directions. The result is an organic, evolving story where everyone can participate.
Protagonize uses the Yahoo! User Interface (YUI) library quite extensively. Here’s a brief overview of the features that use AJAX calls (thus far — still adding more):

Commenting (add/delete)
Add & remove favourites & page markers (like a bookshelf)
Story ratings
Tag autocomplete
Modal dialogs (login)
Send to a friend
Contact author
Report an item
Protagonize was recently reviewed by Ajaxian, a large Web 2.0 and AJAX web application review site:
http://ajaxian.com/archives/protagonize-choose-your-own-web-20-adventure

YouTube has come a long way since we were one of the first shows to review the site on TV in 2005. But what’s more interesting is how many websites are inspired by YouTube, spinning off their own digital creations. Whether you’re a gamer, scientist, or teacher, there is a YouTube-like place for you online.

wegame.com

scivee.tv

teachertube.com

P = Program Mode

Of the manual control modes, Program Mode is the most automatic of the four — you can adjust a few minor things, but in general this is as close to point-and-shoot as you’ll get. If you’re just shooting general pictures without specific effects in mind, this is always a good place to start.

A = Aperture Priority Mode

The aperture is the size of the opening in the lens that allows light to enter the camera, and it’s measured with a numerical rating that’s also referred to as an “f-stop” — the lower the number, the wider open the aperture is (and consequently the more light is allowed to enter ). When you choose Aperture Priority mode, you’re specifying to the camera what the aperture size MUST be, and the camera will then calculate the proper shutter speed to allow for the proper exposure. The main reason to choose Aperture Priority mode is to adjust depth of field — the more wide open the aperture is, the more blurred items in the background will be, and the more closed it is, the more everything in the shot will be in focus. (Note: on Canon cameras this may show up as Av)

S = Shutter Priority Mode

On a camera, the shutter is opened when you take a picture, allowing light coming through the lens to hit the film — the longer you hold it open, the more light will be gathered. With modern digital cameras, the film is replaced by a sensor, but the concept is the same…the longer you monitor the sensor, the more light it will receive. When you switch to Shutter Priority Mode, you’re telling the camera how long you want the shutter to remain open (or how long you want the sensor to gather light), and the camera will calculate the size the aperture should be to ensure a good shot. There are a couple of reasons to choose Shutter Priority: for something that’s moving really fast, a faster shutter speed can capture a freeze frame of the action (while a slower shutter speed can capture motion blur). You can also use a longer shutter speed to compensate for low light conditions, if you can’t open up your aperture any wider. Be warned, though: long exposure shots almost always need to be steadied with a tripod to avoid becoming a blurry mess. (Note: on Canon cameras this may show up as Tv)

M = Manual Mode

There are some cases where the other three manual settings just won’t cut it to achieve the effect you’re looking for. That’s what Manual Mode is for: it gives you full control over both the aperture and the shutter, so you can adjust both to your liking. So for example, if you want to capture motion blur in a waterfall but Shutter Priority gives you a brighter shot than you’d like, you would keep the same shutter setting in Manual Mode but narrow the aperture.

Cameras shown:

Olympus E-3
www.olympusamerica.com
$1,699 (body only)

Canon Digital Rebel XTi
www.canon.com
$750 (w/ 18–55mm lens)