What is new in Version 5.0.1?
Mainly bug fixes. Check out http://www.doublecloud.org for details. 

What is new in Version 5.0?
vSphere 5.0 support: http://www.doublecloud.org/2011/08/what%e2%80%99s-new-in-vsphere-api-5-0/
A few bug fixes since 2.1 release

What is new in Version 2.1
vSphere 4.1 support: http://www.doublecloud.org/2010/07/whats-new-in-vsphere-4-1-api/
Bug fixes

What is new in Version 2.0u1
Bug fixes:
2814793  	 ClassCastException in XmlGen.java
2819624  	 Caching: NPE occurs repeatedly in watcher thread
2823427  	 customize vm causes cast error in XmlGen.toXML()
2825430  	 DistributedVirtualSwitch#getSummary() has incorrect impl
2825433  	 ResourcePools occasionally returned as VirtualApps
2837427  	 AddDVPortgroup_Task should return a Task object
2837428  	 moveDVPort_Task should return a Task object
2839209  	 Caching: Flood of exceptions when authentication fails
2840733  	 HostPatchManager.uninstallHostPatch_Task() is missing
2898611  	 HostProfile.updateHostProfile() should return ProfileExecute
2903501  	 NullPointerException when call findAllByUuid
2907215  	 Missing network traveral in PropertyCollectorUtil.java

What is new in Version 2.0

0. vSphere 4.0 support
1. High performance Web Service Engine to replace AXIS.
2. POJO Data Objects and Java Enum Types 
3. REST Client API (experimental)
4. Caching framework (experimental)
5. Samples using the APIs

What is new in Version 1.0
1. Some code refactoring with ManagedObject.java and PropertyCollectorUtil.java
2. Added getPropertiesByPaths() which can retrieve multiple
   properties of a single managed object at a time. The result is returned in a Hashtable.
3. Added retrieveProperties() method into the PropertyCollectorUtil so that you can get multiple
   properties on multiple managed objects in a single call.
4. Added a new sample to show how to use the retrieveProperties() API.

The summary of bug fixes in Version 1.0 Beta

1. Surfaced the exception up to the caller other than printing out error message.
	https://sourceforge.net/tracker/?func=detail&atid=1073396&aid=2031543&group_id=228007
2. Added three missing methods to the ListView managed object.
3. Added 18 more samples into the release. Tom Elliot contributed his first sample.
4. Changed the VMClone.java to accommodate the change of #1.
5. Added a public method getPropertyByPath() to ManagedObject.
6. Added toString() method to the ManagedObject