"install Chrome" Ad on IE8

"Because Google can detect which browser is accessing its page, thanks to the User Agent string.

Firefox already uses Google as the default search provider, which most people will not change. This means the Firefox users will give revenue to Google thanks to the ads displayed next to the search results.

IE8 by default uses Bing as search engine and thus does not redirect searches and money to Google. That's why you see the ad on IE8."

"well there's loads of html/css/js specs that internet explorer just doesn't follow.
therefore if google wants a better web, supporting open standards, then webkit/gecko/opera is the way to go.
also, there is the 'default search engine' issue as explained by Snark."