I'd be outraged. Google doesn't do that. Blackberry doesn't. Windows doesn't. And there is no charge for upgrades on my iMac accept of course going from leopard to snow leopard.
(Yes I am pissed today because I thought there was some great new thing from iTunes and all we got was the Beatles. Peachy. )
My understanding is the first major upgrade on each device is free. the next you pay for.