$item = gi "/sitecore/content/Habitat Sites/Habitat Home/home" -Language 'en'

$sharedLayoutField = $item.Fields[[Sitecore.FieldIDs]::LayoutField]
$finalLayoutField = $item.Fields[[Sitecore.FieldIDs]::FinalLayoutField]

$sharedLayoutXml = [Sitecore.Data.Fields.LayoutField]::GetFieldValue($sharedLayoutField)
$finalLayoutXml = [Sitecore.Data.Fields.LayoutField]::GetFieldValue($finalLayoutField)

$sharedLayout = [Sitecore.Layouts.LayoutDefinition]::Parse($sharedLayoutXml)
$finalLayout = [Sitecore.Layouts.LayoutDefinition]::Parse($finalLayoutXml)

$sharedLayout.Devices[0].Renderings.Count
$finalLayout.Devices[0].Renderings.Count