With this plug-in installed, web developers need only one line to switch from IE's Trident engine to CF:
Or
the user can add the cf: prefix in the URL to use CF to render the page.
Watch this video for a brief introduction.
So why brother to bring these stuff to IE? With CF, web developers can stick to HTML5 and Javascript (and Ajax) to build rich internet applications (RIA) without using proprietary technologies like Silverlight, Adobe AIR (which based on Flash) and Sun JavaFX.
The results? The bar for developing RIA is lowered. The Web is less depending on individual vendors. More devices can enjoy better web experience without whether proprietary plug-ins are available in specific platforms.
Both Webkit and V8 are open source. If the future of Web (Web 3.0) is built around HTML5 and JavaScript, we can imagine that the OS game is over (at least changed). Who will care what OS is running when all the functionalities can be obtained from the web ? Most people will definitely look for faster and cheaper (or even free) alternatives unless you are gamers or professionals that rely on sophisticated software to learn your living.
There is a long way to go there but this is the vision behind Google Chrome OS. Intel is also working on Moblin, a Linux based lightweight OS which can be booted within seconds.
The driving forces behind HTML5 are Google, Apple and Mozilla (the browser makers other than Microsoft). Microsoft has low motivation in supporting HTML5 as Silverlight is their answer to the future of the Web. However, Microsoft doesn't release Silverlight for other platforms except Mac OSX. It only provides support for open source effort - Moonlight, which brings Silverlight to Linux.
Recently, Microsoft and Intel team up to bring Silverlight to Linux targeting Atom platform. Suddenly, the Moonlight project seems becoming irrelevant.
The only selling point for Silverlight is the multi-programming languages support provided by the lightweight .NET runtime being a part of Silverlight.
Chrome Frame official site: http://code.google.com/chrome/chromeframe/