Oh how I wish it could be that easy. Our problem is that we have over 150 machines that need to be checked and while we have images for each type of system (oh ya we have 4 different computer types that are used so that means 4 different images), we have a problem when a system goes down and we have patched but not taken an image yet that things start to get convoluted.
So the best way i see right now is a system such as this where I check each system against a list and see what systems need what patch.