Ideological concerns aside, I don't really see that much of a problem in law enforcement hacking personal computers. For one thing, it just might stimulate the crypto and computer security industries. For another, there shouldn't be anything to hide, right? I mean, if they start cracking down on pirated software and whatever, that might be a little bit of an issue... ...but not if you don't pirate. ;)
As ususal with privacy concerns, that is decidedly not the point.