A second build of the successor to Microsoft's Windows XP appeared on the Internet late last week but Windows watchers who tested the software don't see major advances to get excited about yet.A second build of the successor to\u00a0Microsoft's Windows XP appeared on the Internet late last week but Windows watchers who tested the software don't see major advances to get excited about yet.When it hits the stores at the end of 2004 or in 2005, the software, code-named Longhorn, should be one of the most important new releases of Windows that the company has ever put out. A big change will be the new Windows Future Storage (WinFS) file system, based on SQL Server technology and designed to give users a direct route to data, making the physical location of a file irrelevant.The new file system wasn't part of Longhorn build 3683 that surfaced in November, and neither is it part of the latest leaked version, build 4008.\u00a0The new build shows mostly evolutionary, not revolutionary improvements over the earlier build, according to Windows experts including testers with\u00a0BetaNews and Paul Thurrott's\u00a0SuperSite for Windows.WinFS replaces the NTFS and FAT32 file systems used in current Windows versions. Before appearing in Longhorn, WinFS technology is expected to premiere in a new version of Microsoft's SQL Server database, code-named Yukon, due later this year.Bits of WinFS functionality, however, are in build 4008, and can be seen for example when browsing media files. Instead of displaying the contents of specific folders or directories, such as "My Music" or "My Images," Longhorn lets users view files indexed from various physical locations, the testers report. The search feature has also been simplified.Although all testers mentioned the emerging WinFS functionality, they are more impressed by the improved setup utility and procedure for the software. Installation is handled by the new Windows Preinstallation Environment, a small operating system that is loaded into the RAM of a PC. Longhorn installs without user interaction in about 20 minutes, a big improvement over current Windows versions, which take about an hour to install.Also apparent in Longhorn is Microsoft's multimedia push. The latest leaked alpha version has an incomplete "My TV" application, deeply integrated media player and support for creating photo albums, akin to Apple Computer's iPhoto, testers reported.The missing file system is only part of the unfinished work on Longhorn. Another part is the user interface, which is expected to be 3D and video-based.Testers agree that the final version of Longhorn will look very different from build 4008. That is also why Microsoft, which confirmed the authenticity of the leaked Longhorn build, won't talk about the product."The technology at this stage in no way represents what the final version of the product will be. The release is still far away," said a spokeswoman for Microsoft.