Here's the real reason why Apple is sue-happy, especially against Samsung. They must have seen the future, and it didn't look pretty. According to Juniper Research's estimates, the Q2 fiscal 2012 is a perfect example of how Samsung is dominating the competition. Samsung posted sell-through numbers that were double that of Apple, with 52 Million smartphones sold, while Apple's iphone only sold 26 Million and actually missed analyst estimates for the first time in a long time.
A decent chunk of those numbers came from over 10 Million sales of the new Galaxy S III, but of course, Samsung has a large variety of different smartphones out there at multiple price points, including all of their other Galaxy Series. In fact, Samsung is doing so well they are actually hurting sales of other Android manufacturers like HTC. This is the reason why Samsung has quickly risen to the top of the food chain in global smartphone sales. Additionally, their rise has been at the expense of other manufacturers as well, including RIM with only 7.4 Million devices sold and Nokia (the former number one smartphone maker in the world), who is down to 10.2 Million sales.
Of course, it is important to take a step back and remember that the iPhone 5 will be coming out in September or October of this year, and that quarter Apple will likely surge back strong. Still, for Apple, it must be disconcerting to see Samsung thoroughly trouncing them in sales by such a huge margin.