I'm sorry if I missed it, but I don't hear anything lately about Apple's patent on multi-touch. They've sued Palm for using it on the Pre, and now Android seems to use it too (I thought they were "friends" with Google): link
Meh. Patent law professors are nearly useless for real-world situations. Sure they can wax philosophical about the theory behind patent law, but that isn't as relevant as the opinion of practicing patent attorney familiar with both Palm and Apple's patent portfolios.
what would apple gain by suing? Other than far more negative attention as being a bully. I would think apple would need to be wise in legal dealings as they are not a small company and if they start suing companies not as financially strong the may draw attention and be accused of stiffling competition