The overhead of these phone manufactures comes from their horrible customizations and differentiation practices. I find the idea of paying $10 for the privilege of updating the OS just so I can get the new version of Sense, or TouchWiz, or MotoBlur, or whatever Sony runs now repugnant. I think this idea pushes the market in the wrong direction.
The fact that volunteers create functional ICS installations shows that it doesn't take time or money to get ICS itself running. The vendors themselves add cost by leaving their taint on every interaction I have on the phone.
And the article itself says "OEMs that want to engage in paid updates should have a bootloader unlock solution for users that want to update on their own." with no reasoning at all besides it would make the writer feel warm and fuzzy.