VMW makes server consolidation simple. They are by far ahead of anyone else. They can talk about cheaper competitors, but once you've integrated a platform (like vmware) It is a giant pain in the ass, as well as expensive to just switch. Everyone I know that works with it loves it, and it's getting put in major corporations. It will grow and grow.
It's hard to say, because I believe that you can use different hardware with VMWARE. The thing about Microsoft that sucks is that you can only use it with Microsoft. With VMware U can use Unix, or Novell as well as microsoft. I can't really tell you what effect it will have on those though.