Unified?
How can something that is not open and has at least three parties be unified?
Let's see:
Cisco IOS=closed source
VMWare ESX=closed source
EMC Storage=closed source
Windows=closed source
Redhat=partly closed source
Looking at this list we will have at least 3-4 different companies involved (counting EMC/VMWare as 1 or 2).
Let's see Sun's offer:
OpenNetwork (crossbow) = open source
xVM Server (xen) = open source
OpenStorage (zfs) = open source
OpenSolaris = open source
Best of all, I can get everything from one player, and still run Windows and Linux on top of it.