Chrome doesn't come preinstalled on any OS that I know of. So you're suggesting that users think that they, "Used google to download google so they could do searches on google?"

Yes. I witnessed a user who uses Chrome for Google and IE for everything else. She thought she had to use Google browser to use Google, because Google told her so -- with upgrade to Chrome campaign.

I've started seeing it prejnstalled on a few machines and Google has rather obvious marketing on the Google homepage, enouraging you to 'upgrade to chrome'.