I was made aware that my ESXi-Customizer-PS script fails when running with the new PowerCLI version 5.1. With this version VMware made changes to the ImageBuilder object model (dropping the SoftwareChannel object) that broke my script.
So I fixed it to work with both versions 5.0 and 5.1 of PowerCLI. Please download the new version (1.4.1) from my Google Code page!
Update (2012-09-27): Extended testing of my script's version 1.4.1 revealed that there are problems with handling package dependencies that might occur e.g. when adding certain HP hardware drivers. I just added a quick fix for it and came up with version 1.4.2: It now uses the -Force switch with the Add-ESXSoftwarePackage commands which will add all packages regardless of failing dependencies. Don't worry: If there are real unfulfilled dependencies in the ImageProfile after adding all packages then you will get a warning at the end when the ImageProfile is exported to an ISO file or Offline Bundle.
If you have already downloaded version 1.4.1 then please replace it with version 1.4.2 a.s.a.p. please!