Luís Rato
Get UserProfile and set property value with PowerShell
Get a UserProfile
::Loadwithpartialname("Microsoft.Office.Server");
$site=new-object Microsoft.SharePoint.SPSite("http://sharepoint-site-url");
$serviceContext = Get-SPServiceContext $site;
$site.Dispose();
$upm = new-object Microsoft.Office.Server.UserProfiles.UserProfileManager($serviceContext);
$userProfile = $upm.GetUserProfile("domainusername");
Set property value
$userProfile.Value = "property value";
$userProfile.Commit();