I see a lot of people trying to automate test tasks with Vix API. Well, we were too 
That's how I ended up writing VMWareTasks.
Today I am happy to announce the open sourcing of RemoteInstall test framework, entirely based on VMWare. Targeted to testing installers originally, it has grown in a nice test framework. It is:
Designed for continuous integration with CruiseControl and CruiseControl.NET.
Supports VMWare Professional 6.5, VMWare Server 2.0 and Virtual Infrastructure (ESX, etc.) with VMWare VIX 1.7.0+.
Supports running multiple installers on multiple virtual machines with multiple snapshots.
Command line, configuration file driven execution.
XML and HTML logging with pretty xsl-tranformed output including custom merged results.
Capable of executing user-defined command-line, virtual machine and virtual machine snapshot tasks.
Capable of combining results from multiple runs and user-defined tasks.
Automatically collects installation logs clickable in the results summary.
Copies user-defined files and folders from/to the virtual machine.
Supports horizontal scaling with parallel execution against multiple Virtual Machine hosts.
Itegrates and remotes unit tests from unit test frameworks, including NUnit and JUnit.
Supports some distributed test scenarios with multiple virtual machines and snapshots.
Check it out. Maybe you don't need to write that tool after-all
http://remoteinstall.codeplex.com/