Microsoft plans to release the first beta of the next version of Internet Explorer in the first half of 2008, and said that IE 8 has passed a key Web standards test that ensures the  browser won't "break" the Web.

according to the IDG News Service: IE8 has passed the "Acid2 Browser Test" from the Web Standards Project, which shows whether a browser renders a Web site in a certain way. If the browser renders the site correctly, it means the browser supports certain accepted Web standards.

Microsoft developed IE before some Web standards such as CSS (Cascading Style Sheets) and RSS (Really Simple Syndication) were developed, and so older versions don't support some current standards. Developers would write applications to work with IE rather than to support Web standards, since the browser was the de facto standard for surfing the Internet for so many years. Microsoft also was lax in updating IE to meet the demands of Web standards, since there was little competition in the browser market for years.

At Microsoft's Mix'07 conference in Las Vegas in May-2007, IE platform architect Chris Wilson recapped Microsoft's development priorities in the making of Internet Explorer (IE) 7 and outlined some of its goals for the next version of its browser.

Microsoft officials did share some broad and open-ended design goals for the next version of IE at Mix ‘07 in early May. Chris Wilson, Platform Architect for IE, said Microsoft was investing across layout, object model and Ajax development with IE 8.0 and that IE 8.0 would be more compliant with CSS 2.1 layout standards. He also said Microsoft was planning to allow developers to add extensions to IE more easily. Wilson said to expect Microsoft to be investing across layout, object model and Ajax development fronts in IE 8.0. Specificially, Wilson said Microsoft is investing in making IE 8.0 more compliant with CSS 2.1 layout standards. Microsoft also is working to make the IE 8.0 object model more interoperable with that used by other browsers, and is looking to provide more client-side application programming interfaces (APIs) to support local storage for mash-ups.

In May, Microsoft reps said they were looking to release the next versino of IE two years

after IE 7.0 — which would mean some time in 2008. If that date is still good, it seems like the new release should be in testing outside of Microsoft at this point. (Anyone out there in a private alpha/beta/CTP?) Or maybe there’s no word because the next IE has been pushed back? some of more details can be found at http://www.news.com/Microsoft-hints-at-general-plan-for-IE-8/2100-1012_3-6181334.html?tag=nefd.top  and also at http://arstechnica.com/news.ars/post/20070502-microsoft-drops-hints-about-internet-explorer-8.html

also according to the some other resources: The IE (Internet Explorer) development team is also pledging that while IE 8 will deliver advancements and enable Web developers, designers, and Internet Content Providers to develop across multiple platforms and versions and provide richer user experiences, it will not break the Web as happened with the current IE 7 due to the improvements it made to CSS (Cascading Style Sheets). In a move the development team is citing as a milestone on its blog, it says that IE 8 in standards mode now correctly renders the "Acid2 Browser Test," which determines how well a browser works with several different Web standards.

also; according to the msinsider bloggers; Some details of Microsoft internal blueprints for so called “Windows Vienna” and “Internet Explorer 8” managed to get leaked on the Internet by Channel9 regular... Reading the blueprints gives you an idea about how the inside of Microsoft works. It seems Microsoft is well aware about the existence of Firefox and Linux and plan to leverage their technologies in their new products, and they aren't the least bit secretive about it (at least internally). Some features planned for Internet Explorer 8 include “undo close tab (like Firefox)”, and “saving and restoring sessions (like Firefox)”. For Windows Vienna, expect “virtual desktops (like Linux)”, and “the ability to rearrange items on the task bar”. Keep in mind attributions are copied verbatim from Microsoft's task list. In an interesting move Microsoft will make the next version of Windows theming completely customizable, the internal e-mail says. The most interesting about the new version of Windows is virtualization will be prominent for “legacy apps”, all applications not specifically written for Window Vienna or in .NET will be run on a separate virtual machine. This is comparable to how Mac OS X handled Mac OS 9. Windows Vienna will also feature “Windows Core”, the ability to separate GUI and console from each other as in Windows Server 2008. They Expect to see “Windows Vienna” on store shelves some time in 2009. The final name, however, has not been revealed.

some of the screen-shots of IE-8 can be found at following links

channel9.msdn.com/ShowPost.aspx?PostID=250078

http://img152.imageshack.us/img152/4493/ieribbon1xv4.jpg

http://img244.imageshack.us/img244/4271/ieribbon3ph3.jpg

http://img152.imageshack.us/img152/6082/ieribbon4dk1.jpg

also; more details and blog posts can be found at http://channel9.msdn.com, http://blogs.msdn.com/ie/archive/2007/12/05/internet-explorer-8.aspx and http://www.internetexplorer8.net