[MatthewPhillips]

That you're only breaking a small section of a site is a false assumption. You really have no way of knowing that. You will be breaking the entire site in the case of a site that writes all of its content using JavaScript obtain from that resource. This is fairly common with jQuery fallback document.write scripts.

document.write() calls are dependencies of the site, in many cases. Some times they are just worthless ad stuff, but you shouldn't make any assumptions here. Not breaking the web should be the priority.

[EdwardDiego]

Hehe, as a slightly jaded participant in the advertising industry, I note that Chrome only breaks technologies used for ad-serving that Google's stopped using.

That said, I'm glad they are doing this, because finally we can wean our advertisers off their document.write obsession.