Reinvention
Traditionally you could run a large number of services on a single host OS... However, through a combination of security concerns, poorly designed operating systems (mostly windows - lack of chroot) and poorly designed applications, it's no longer fashionable to install multiple services on a single OS.
Virtualization (yes its been around a long time - often as a glorified chroot), was primarily useful for hosting environments where each customer could have root on their own virtual environment.
I personally am not a fan of vmware for a number of reasons...
Proprietary management/console tools, tying you in to windows (they used to support linux but not anymore)... By contrast, KVM can be managed via SSH and VNC. Also seems rather foolish to create a dependency on windows, when microsoft are trying to kill them with hyper-v.
Expensive - they give you the base hypervisor for free, but its pretty useless on its own... any remotely useful features are nickle&dimed... Considering most of the competitors are free, vmware is massively overpriced.
Flakey - vmware esx seems to use some pretty crufty hacks to improve performance, but these are only tested on specific guest os... If you want to run something else, or build your own custom kernel etc you can have all kinds of problems.
Questionable licensing terms - their EULA prohibits benchmarking, why would you do that unless you have something to hide? The obvious reason is because vmware performs very poorly compared to its competitors, and they don't want that fact made public.
Their stated reason that they don't want erroneous benchmarks put out is ridiculous, their own benchmarks are highly likely to be erroneous too - in order to make their product look better... What users need is a range of benchmarks from different sides so users can draw their own conclusions.
Personally i feel vmware have no future, they are the new netscape... Sure, they were a pioneer in virtualization on x86 and were once the only game in town and could rake it in. Now, they're a dinosaur, charging for a product everyone else gives away for free...
They will lose windows customers to microsoft, as hyper-v comes with windows, and will offer better support for windows (and who knows, ms may even modify windows so as to cause problems when running in vmware - wouldnt be the first time)...
They will lose linux, bsd and solaris customers to kvm and xen, they have already alienated the linux users by dropping support for the console and forcing users to run windows management hosts...
They won't make much of a splash in the cloud hosting arena, because the idea of the cloud is to scale and that doesn't work when your paying through the nose for software...