Versions 1.0 and 2.0 was to make lots of small improvements in addition to the more publicised new features. Donwload
PowerShell, 1.0, was a separate download which could be installed on Windows operating systems from Windows XP for clients and Windows Server 2003 for servers.
Number of cmdlets
Supported .net framework
PowerShell 1.0 required the .NET Framework version 2.0 to be installed first. This was not included as part of Windows Server 2003 or Windows XP>
Integrated Scripting Environment (ISE) PowerShell version 2.0 a new tool, the Integrated Scripting Environment (ISE), Earlier with PowerShell version 1.0, the systems administrator worked either from the familiar blue console

With V3.0 Microsoft come up with chnages in Switches
Along with the required Name parameter, the script takes several optional Switch parameters to modify the output.
1. You can list parameters that the cmdlet shares between versions with the parameter "Common".
2. You can list parameters that existed in version 2, but which are not in version 3 with the parameter "Removed".
3. You can list the new parameter names and type with the parameter "Detailed".