Thanks for reporting this; it appears to be a bug in Chrome v21, which also isn't displaying other Google-hosted images in our site for some reason (such as the Buy With Google buy-now button and Google Checkout CC-logo image on our Google Checkout demo page: http://www.e-junkie.com/ej/google-checkout.htm ), so I've submitted a bug report to Google about it. Hopefully, with Chrome's rapid release cycle, they'll get this fixed and roll out the bugfix in Chrome v22 coming soon.
Meanwhile, we've hacked-in a workaround, so if our cart detects the buyer is using Chrome, it will show a Buy With Google checkout button image that's hosted on our site, rather than pulling the button image directly from Google.