This too will generate massive data transfers and giant invoices, which will continue to cause iPhone/iPad users to be totally offline/no email as soon as they leave their home country/city ("off when roaming") to avoid huge bills.
But, like an Indonesian helper, they will continue to use pay-per-use 1990's SMS technology!
If you want to travel with a laptop: Bring your laptop, not an iPhone/iPad.
If you want to use email without a laptop: Get a Blackberry, not an iPhone/iPad.