In the following manifest, is it necessary to change the version
attribute of the assemblyIdentity
element if the assembly version is specified in the
The point of the assembly information is to uniquely identify your application to Windows and it's components. This is similar to how .NET uses filename + version + ID generated + target processor arch to identify assemblies uniquely.
If you choose not to change it then Windows components may not see new versions of your application as uniquely different from old versions.
More information on the Application Manifests MSDN page.