Microsoft’s HyperVisor software is new to the market. While it always takes time for a new product to have the bugs worked out it seems that Microsoft’s offering the visualization market is making waves even at this early stage. VMWare is surely aware of this and is going to working on proving that their product is superior in the coming months. Either way, competition in any market makes the product better for consumers.
Check out this article that discuss the various high level differences between VMWare and MS’s HyperVisor