Chrome isn't an IE killer, its a Firefox killer. Why? because Chrome (like IE) is a chosen browser. IE is a default.

Most Firefox users have chosen to use it. Downloaded it. Installed it. Tried it & use it. Most IE users have not.*

Once someone is making a choice, you can reach her. Say 'but wait there's more.' IE users aren't even going to know about Chrome. They won't ever be consciously deciding between browsers. If they are, resistance to change is a big factor. If Chrome becomes demonstrably better choice, it will be chosen. But only by those making a choice. Everyone else isn't listening.

So basically FF users make a choice & Chrome gets to make its pitch. IE users don't. Product similarity has nothing to do with it. Its market similarity that runs this show.

*Obviously some IE users made a choice. They're in the FF category.