The final amount Samsung pays Apple will be far less than $1 billion. The amount that Apple already paid Samsung in higher part prices because of "unforeseen litigation" will continue to have been $1 billion. This is already a Pyrrhic victory for Apple, and will become more so when it goes back to the lower courts and the amount is reduced even more.
It's also getting rather silly, because the phones involved are no longer for sale, Samsung no longer uses the version of TouchWiz that looks like the iPhone (courtesy of Google and others that have made the Android UI more standardized across Android devices, so working like an iPhone makes things feel odd). I mean, even the phones themselves are probably sitting in drawers and landfills by now (Samsung Galaxy S2, anyone? I think that was the LATEST phone involved).
In the end, it will probably all end up for naught - though there may be regulatory changes for the worst - if a patent lawsuit takes years to resolve, by the time it is resolved, the infringement is no longer valid because the products are long obsolete. This may mean the way around it is to simply a war on attrition - violate the patent now, then just argue and argue until the whole issue is moot.
Heck, I think even the patent behind it has expired by now - (it's a design patent, which only have a short 5 year lifespan).