Microsoft seemed to have two key goals in developing this version of IE. First, was its move towards embracing standards. Long criticized for marching to the beat of its own drummer (or in this case its own specifications), Microsoft has drifted much closer to the middle with this release. Key among the standards being supported is HTML5. Amid the scuffle between Apple and Adobe and the battle over support for Flash, HTML5 has emerged as the universal way for developers to offer rich media experiences to users across all platforms. Plug-ins like Flash and Silverlight are not dead by any means, but we will definitely start to see a strong shift to HTML5 in the very near future. When you consider popular browsers from the desktop side (IE) to mobile (iPhones support HTML5) are all offering support, you can bet developers will take advantage of it.
The second goal in the development of IE9 is a very dramatic shift in the way browsers work in general. The philosophy for Web browsing has long been that the experience should be largely the same across any device. This meant that as computers became more and more powerful, the Web browser wasn't taking advantage of any of the hardware advancements. This is criminal when you consider the browser is where most users spend a large portion of their time. Microsoft has changed this with IE9 and completely flipped the script. IE9 actually takes advantage of the computer hardware on which it's running-most specifically the graphics processing power-to speed up and improve delivery of text, graphics and video. The result is a robust application that moves the focus away from the browser and to the website. Developers working in the Web environment can finally start to take advantage of powerful native hardware and deliver really robust applications.This might not be a lot of help to users with mobile Web browsers, but it most certainly means we'll see a lot more powerful Web applications.
Microsoft added some other neat features that show its desire to take the focus away from the browser and move it to the website. Things like pinned sites and jump lists (which will both be familiar to you if you're a Windows 7 user) give users the feel that websites are practically native applications. This apparent desire to make the browser more transparent makes me really feel like the company is planning monumental changes at the operating system level. People have been wondering what the future for the desktop operating system is for years. If Microsoft is already making users feel like websites are native applications, and it is offering its core Office applications in the cloud (Office 365), how much longer is it before the OS is literally just a Web browser? I think we'll see a Windows 8 at some point, but I really think beyond that the Microsoft operating system will look nothing like we are used to.