Could this iPhone with a universal SIM work the same as a multi network MiFi?

Does the universal sim mentioned in this article mean that it would be possible to have a tethered iPhone not locked to any one network? It could thus potentially work like a multi network MiFi. Imagine an app that tells you which data signal has the fastest speeds and allows you to switch between networks seamlessly. Perhaps Apple will build it into the OS..?

I know that there are broader implications for the market if Apple does release such a device. But it just occurred to me that you could potentially manage multiple pay as you go accounts for data with such a device and always have a data connection. Such a feature could lead to a more ubiquitous mobile web experience for many of us. This I think would be possible in the UK where most places, apart from the remotest areas, allow you to get at least some data signal from one of the five main networks.