Nice one for the comments guys. I agree, I'd be happy to pay a little for the extra development. But if the HD versions are just upscaled versions, will they need that much development? and if not, are you happy to pay for them?
5 times the price seems ridiculous, is this because the iPad is bigger and more sophisticated, giving it a more powerful console-like status meaning people will pay more, when compared to them spending 59p on a bit of a laugh on their phone?