Phil Randal did an awesome job by more or less completely rewriting the check_esxi_hardware Nagios plugin. He added a lot of new functions:

• Parameters
  The plugin can now be launched like other Nagios plugins with parameters for destination host (-H), username (-U), etc.
  The old way to use the plugin is still possible.
  
  
• Auto Hardware Detection
  A switch has been added in the plugin to (try) auto-detect the server hardware by using the CIM information. It is still recommended to use the correct hardware type though.
  
  
• Perfdata
  With the new optional parameter -p (or --perfdata) it is now possible to let the plugin show perfdata of the server hardware. Useful for graphics like Nagiosgraph or PNP4Nagios.
  
  
• Web-Links to Hardware Doc
  For Dell servers it is possible to add the switch -I (--html) which will add an web-link to the hardware documentation of the specific server.