Vista Server: Limited Scope

We heard last week about Vista Server being optimized for the high-end Itanium server, and not running on anything else. That already raised enough questions as to what will happen to existing 2000/2003 Servers as they became phased out. Now, even more questions are going to be raised as Microsoft states that the scope of Vista as a server will be quite limited indeed. Apparently, it will be designed for three particular workloads, and those workloads only:

"Windows Server 'Longhorn' for Itanium-based systems is designed specifically for database workloads and custom and line-of-business applications," Microsoft said.
Itanium is not a popular chip, and it seems a bit of an anticlimax to have a server operating system for it which such a limited range. Windows Server makes up a substantial portion of the server market for x86 (around 30% worldwide), and this doesn't seem to be making them any headway. What oh what is Microsoft up to?