The BBC recently published an interview with the jury foreman of the US Apple vs. Samsung trial on how they treated prior art. Here's a bit of what he said:
Prior art was considered. But the stipulation under the law is for the prior art to be sufficient to negate or invalidate Apple's patents in this case, it had to be sufficiently similar or, more importantly, it had to be interchangeable.
And in example after example, when we put it to the test... the hardware was different, the software was an entirely different methodology, and the more modern software could not be loaded onto the older example and be run without error. And vice versa of that was also true.
... when we looked at the source code - I was able to read source code - I showed the jurors that the two methods in software were not the same, nor could they be interchangeable because the hardware that was involved between the old processor and the new processor - you couldn't load the new software methodology in the old system and expect that it was going to work. And the converse of that was true.
He seems to have some strange ideas in which changing the processor architecture (or something similar) would mean that prior art wouldn't count. Perhaps Samsung needed to simply insert calls to random Android subsystems into its code even if weren't necessary to the operation of the program. Such would be silly and inefficient, but it seems to be the sort of thing that's required to make a legal product in this day and age. See, example, Ars Technica's piece Why Johnny can't stream: How video copyright went insane in which to be legal it seems as though a company wishing to stream free over-the-air broadcast TV to subscribers needs to have an individual antenna and encoding process per client rather than sharing most of this.
The New York Times had the following to say in an article:
... the decision could also create a “minefield” for product designers, in which they are constantly second-guessing whether functions will step on someone else’s patents. Mr. Flora is concerned, for example, that Apple’s patent on the pinch-to-zoom function covers a gesture that now is so common that touch screen products without it would be like cars with square or triangular steering wheels. “It’s very much like a circular steering wheel,” he said."
One big issue there is that, although Apple holds a patent on this sort of thing, Mitsubishi already had demo units showing pinch-to-zoom and bounce-back effects in 2001, before Apple's earliest iPhone prototypes.
Also noteworthy is the fact that Samsung wasn't allowed to show certain evidence against Apple in the US trial. I mentioned before that Apple was being legally required to run ads in the UK saying that Samsung hadn't infringed it's patents, and most other courts seem to be leaning the same way. To quote a letter Samsung released to it's employees shortly after the verdict:
The NDCA verdict starkly contrasts decisions made by courts in a number of other countries, such as the United Kingdom, the Netherlands, Germany, and Korea, which have previously ruled that we did not copy Apple's designs. These courts also recognized our arguments concerning our standards patents.
Take a look at the patents Samsung was convicted of breaking in the US court's decision and ask yourself how many of these are really worth worth protecting.