This isn't the only chunk of patents that Apple is looking to pick up -- the bankrupt Nortel Networks is also trying to sell off a swath of 4,000 patents worth over $1 billion all together, and Apple is reportedly interested in buying at least a few of those. Microsoft and Google are also aiming to pick up some of Nortel's patents.
And all of these patents are just more ammo in a few different ongoing lawsuits, between Apple and other cell phone manufacturers. At this point, we're getting into a level of abstraction that seems pretty far removed from the reason patents were invented in the first place. But as long as Apple can gain an advantage by patenting as many technologies as possible and buying as many patents as it can, it'll play the system as much as is legal.