Microsoft pleased the world at large by announcing a free upgrade to Windows 10 for consumers with Windows 7, 8, and 8.1. Unfortunately, Microsoft will not be extending that same offer to enterprise users.
Microsoft has released a statement on the issue, "Windows 7 Enterprise and Windows 8/8.1 Enterprise are not included in the terms of free Windows 10 Upgrade offer we announced last week, given active Software Assurance customers will continue to have rights to upgrade to Windows 10 enterprise offerings outside of this offer - while also benefitting from the full flexibility to deploy Windows 10 using their existing management infrastructure."
Microsoft is releasing a new two-tier enterprise updating feature. The 'Current Branch for Business' feature allows users to defer new updates for 120 days while they are thoroughly tested in client versions of the operating system. The operating system will still receive up-to-date security updates.
The 'Long-term Servicing Branch' will operate in similar fashion to current Microsoft update cycles, with the latest security and critical updates delivered as usual, and a five-year update cycle. This will ensure a standard OS that requires no new training for an extended period of time.