Hmm -- if accurate, this would suggest 1) Google is taking IE8 very seriously, and 2) Google, despite providing major funding for Mozilla.org (and recently renewing its agreement with Mozilla.org for another three years), apparently can't meet its objectives exclusively through Firefox.
The browser, called Google Chrome, is likely to be announced soon, according to these people. They say software is designed to make it easier and faster to browse the Web, by offering enhanced address-bar features and other elements that are very different from those on other browsers. The product will be open-sourced, meaning others can modify the code.
More details (and no wsj.com subscription required) on CNet