LG doesn't want life to be good (all pun intended) for Sony. LG has filed a complaint against Sony with the US International Trade Commission (ITC) claiming that the PlayStation 3 and Bravia line of television models infringe four Blu-ray Disc patents.
LG is seeking a permanent ban of the PS3 from the US market. They've also filed a separate lawsuit with the US District Court in the Southern District of California which covers other non-PS3 devices such as PCs and digital cameras. This lawsuit seems to stem from Sony's complaint about various LG smartphones last December in which the ITC is already investigating.
This could be seen as a form of revenge, which is both good and bad to see that a company as large as LG can have it's feathers rustled enough to bitch slap Sony like this. MEOW.