If webmasters are now responsible for the other side of the linkage, I haven't read anything about anything.
IANAL*, but it is *obvious* that you aren't responsible for the other side. In front of a judge, on the top of my head I think there's only one case where the court would make you guilty. Say you have a kid's website, targetted to a young audience. One of your links change to a porn page.
You can say that you had no idea that this happened, the 'net is a wild place, changes take minutes to apply, etc... (and you're right). On the other hand, the judge will say that you had to be more careful, and it's your obligation to make everything that you can so your audience doesn't see this kind of thing (and the judge would be right).
You will reply that the parents should monitor their kids internet activities, and that they should have a nanny software to prevent this (and this is a fact). The judge will not care because that's how the USA legal system works in real life, and "moral damages" are stupidly high (and that's a fact too).
So, to answer your question ^_^
There's no new law that I am aware of concerning links. But depending on your visitors, you must do everything that's possible to protect them. And it's not an one-line disclaimer that will save you.
* By this acronym alone you probably know where this kind of news would hit :p