Chrome's sandbox is not equivalent to having a separate jail for every web site. It is designed to prevent web content from attacking non-browser apps and data, not to prevent one web page from attacking another (though Chrome, like all browsers, has other mechanisms to do this).
Chrome does not guarantee one process per tab, or even per origin. If you reach its internal process limit -- or if a page does something like window.open() that gives it a reference to another tab -- then it will render multiple sites in the same processes, not sandboxed from each other: http://code.google.com/p/chromium/issues/detail?id=81877
Chrome does not guarantee one process per tab, or even per origin. If you reach its internal process limit -- or if a page does something like window.open() that gives it a reference to another tab -- then it will render multiple sites in the same processes, not sandboxed from each other: http://code.google.com/p/chromium/issues/detail?id=81877