Few people paid attention to the following interesting fact: the much-rumored iWatch as well as its now-rumored competitor by Samsung are said to have an internal SIM card.
Both smartwatches will also have Bluetooth that allows them to be linked to the phone.
Let me connect the dots: that's your operator-agnostic dual-SIM solution, if implemented correctly (sorry, cannot tell you much on that as I am not allowed to "promote" TEDIPAY in my blog posts).
Add the forthcoming BEREC 2014 regulation of decoupled roaming in the EU to the equation. Sprinkle with the MVNO business model. Roaming tariffs arbitrage is the icing on the cake which 1bn of travellers can enjoy worldwide.
All that is left is to rub the bottle to let that genie out...
By the way, that's your operator-agnostic secure element too. To be used both for contactless payments and e-commerce (two-factor authentication).