Are you sure you're running Powercli and not just windows powershell from the powercli directory?
To be sure you're running Powershell with the vmware cli snap in enter this in your start>run box:
C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe -psc "C:\Program Files (x86)\VMware\Infrastructure\vSphere PowerCLI\vim.psc1" -noe -c ". \"C:\Program Files (x86)\VMware\Infrastructure\vSphere PowerCLI\Scripts\Initialize-PowerCLIEnvironment.ps1\"
Thats for the 32bit version. Or try running it from the powerCLI desktop icon. You should see the vmware text load when the powershell window opens. Then try running get-vicommand
