Microsoft System Center 2012 has reached release candidate status. With this release, not only are a ton of new features included, but a new pricing scheme has been unveiled. With the combination of these two things (features and price), Microsoft is setting its aim at VMware. A recent Tech Target article states:
"Microsoft officials made no bones about the competitive target under the new bundling and licensing scheme: VMware, Inc., which by contrast has charged separately and on a per-VM basis for management products such as vCenter Operations and Site Recovery Manager since vSphere 4.1. With vSphere 5, VMware also introduced virtual RAM entitlements.
VMware changed its licensing model in the name of moving users towards a cloud-like, consumption-based licensing model, rather than leaving licensing in the realm of physical CPU sockets. Some users have argued that per-VM licensing is actually more efficient than per-socket licensing, because users only pay for what they need."
So, I guess we will have to wait and see how things shake out with Microsoft and the competition.