Summary
The best new feature of VMware v4.0 (dubbed vShphere) is the inclusion of "FT" - Fault Tolerance. Essentially, if a primary server fails, the 2nd "Shadow" server will seamlessly assume the role of the primary server. This means - zero - downtime. There are certain caveats, such as shared storage is required and a high speed link between the 2 servers is assumed, but IF you need true fault tolerance, this is a great idea.
Analysis
Regarding the cloud; we are still in the concept phase. Essentially, the future of computing - is a vision - where one accesses computing power akin to turning on a light switch.
In my opinion - we have way to go.
There is however a good plan to deploy a disaster tolerance solution with VMware's "SRM" Site Recovery Manager. SRM enables a fairly automated way to work off a "DR" Disaster Recovery site if the primary site fails.
