Windows Whistler is the codename for the first joint business/consumer version of Windows built on the Windows 2000 OS kernel for stability and reliability. To bring the reliability of Windows 2000 to consumers as soon as possible and address the feedback from enterprise customers, Microsoft planned a phased release of Windows XP beginning with the desktop products and followed by the server versions. Windows XP is their first step in the Microsoft .Net vision.
Windows XP Professional will be available in 24 official localized versions in addition to English. In any version of Windows XP Professional, you can display, input, edit, and print documents in hundreds of languages. Users or administrators can set regional preferences, fonts, keyboard layouts, sorting orders, date formats, and so on.
The biggest innovation for multilingual computing is the Windows XP Multilingual User Interface Pack, which is an add–on to the English version of Windows XP Professional. It lets users or administrators switch the User Interface (menus, dialogs and help files) from one language to another. This feature greatly eases desktop administration in multilingual computing environments, and lowers cost of desktop change and configuration management considerably. The Multilingual User Interface Pack will be available in 33 languages.
Windows XP ships with DirectX 8.1, which improves pixel shaders among other things.
The 64-bit versions will only work on newer Intel Itanium based hardware. The 32-bit versions will work on all x86 compatible hardware (such a Pentium III, 4, etc).