Installing Google Chrome on the 64bit Quantal Quetzal is pretty simple.
When you navigate to google.com from the installed Firefox browser, on the right is an "Install google Chrome" link.
Click on it and it goes to a downloads page. Click the "Download Chrome" link, it automatically detects "For Linux (Debian/Ubuntu/Fedora/openSUSE)".
At the next page, select 64 bit .deb (For Debian/Ubuntu) and click the button to proceed.
It will prompt to download google-chrome-stable_current_amd64.deb .
When the download is complete, find it in your downloads folder using the file browser and launch it.
The Ubuntu Software Centre starts and will bring up the Google Chrome page.
Select the "install" button, authenticate with your password and Google Chrome is installed.