" Support for Windows XP will end (on April 8, 2014) before an organization can fully deploy Windows 8, which will take a year after release on Oct. 26, 2012 to mature and gain market acceptance and full app compatibility. Customers can opt for Microsoft's "XP Custom Support," an extension of support beyond the April 2014 deadline, but that support plan is expensive and that money would be better spent moving to Windows 7, according to Gartner.
" If an organization waits too long to upgrade, new applications and software that become available will not run on Windows XP.
" ISVs took a while to become fully compatible with Windows 7. They will take just as long to do so with Windows 8.
" Windows 8 management and security support demands a different skillset for IT groups and will require some time for them to become proficient.
" The Vista effect. The organizations that migrated to Windows Vista had problems, as a result there weren't many that made the move. Therefore many third-party software vendors have stopped supporting Vista. The same thing could happen to Windows 8.