Chris Wilson the IE Platform Architect announces:

"This release contains some great advances in Cascading Style Sheets (CSS) and layout, programming model, performance, reliability, usability and service integration. We are eager to ensure that the transition to Internet Explorer 8 is seamless for you and your audience, and to give you a head start on using many of the new features with your sites and services. We encourage you to test your sites and services, and our platform implementation, and give us feedback!"

If you're an Ajax developer these are the features that matter most to you:

1. 1. AJAX Navigation enables users to navigate back and forth without leaving the AJAX application and could be used navigating a page without performing a traditional full navigation. This allows websites to trigger an update to browser components like the address bar by setting the window.location.hash value, firing an event to alert components in the page and even creating an entry in the travel log.
3. 2. DOM Storage is a simple-to-use method for storing and retrieving strings of key/value pair data. Data can be stored per tab instance for a session or persisted to the local machine. This allows pages to cache text on the machine which reduces the effect of network latencies by providing faster access to pre-cached data. Several innovative uses are possible. For example, use this in combination with the new network connectivity event to allow a page to cache data if it detects that the computer is offline.
5. 3. Connectivity events allow websites to check when the user is connected to the network and receive notification of connectivity changes.
7. 4. Six connections per host instead of two for broadband scenarios and a scriptable property allow for more improved performance by allowing parallelization of downloads in Internet Explorer 8. In addition, this increases functionality by ensuring a request is not blocked to a host if two connections already exist. Websites can optimize their downloads based on a scriptable property.
9. 5. XMLHTTPRequest Enhancements include a timeout property that can be set to cancel the request if necessary, allowing developers to manage the request better.

If you're a mashup DJ check out the new cross domain bits:

1. 1. With Cross-domain Request (XDR), developers can create cross-site data aggregation scenarios. Similar to the XMLHttpRequest object but with a simpler programming model, this request, called XDomainRequest, is the easiest way to make anonymous requests to third-party sites that support XDR and opt in to making their data available across domains. Three lines of code will have you making basic cross-site requests. This will ensure data aggregation for public sites (such as blogs) will be simple, secure and fast.
2. 2. Cross-document Messaging (XDM) APIs allow communication between documents from different domains through IFrames in a way that is easy, secure and standardized.

Although I can't access the white paper or download anything yet they are promising new developers tools:

Internet Explorer 8 includes tools that Web developers need to efficiently debug their sites directly in Internet Explorer. Developers can immediately debug a site's HTML, CSS, and JScript from within Internet Explorer 8, rather than switch between Internet Explorer and a separate development environment.

As we've heard before there are going to be 3 different rendering modes:

• * Quirks - backwards compatibility with IE5 rendering behavior.


• * IE7 Standards - backwards compatibility with IE7 JavaScript and layout behavior.


• * IE8 Standards - latest features, including the CSS 2.1 compliant layout engine and DOM/HTML breaking changes.

There are some new features that end users are likely to care about also Activities and Web Slices.

"Activities are contextual services to quickly access a service from any webpage. Users typically copy and paste from one webpage to another. Internet Explorer 8 Activities make this common pattern easier to do."

They give access to the right click context menu to add super duper web service enabled tool tips, very cool from a usability perspective allowing the user to remain in context while exploring another action.

The other new feature is Web Slices:

WebSlices is a new feature for websites to connect to their users by subscribing to content directly within a webpage. WebSlices behave just like feeds where clients can subscribe to get updates and notify the user of changes.

Well let's just keep our fingers crossed that the download will be available soon.