How many times do I have to repeat myself ?!?
DO NOT compare yourself and your home PC with a large corporation with a large IT department that know what they are doing.
You don't know doodly squat about their network and you don't know doodly squat about their Windows 7/8 migration plans (which I can pretty much assure you they are almost certainly undertaking).
Just stop clinging on to XP.... there is no excuse for home users or small businesses to stay there.
There is no excuse for business to hang on to XP either, probably moreso than private individuals. To do so is putting your business at an unnecessary risk, and any IT department that suggests otherwise is totally irresponsible, and dare I say ignorant.