I don’t know—unless you have a machine with a really fast CPU and/or a lot of memory (e.g., 6 GB of RAM or more), I’d rather run the current version of Google Chrome. Not only is Chrome more HTML 5.0 compliant, but each tab runs in its own process, so if there is any browser crash all you need is shut down the tab to restore normal operation.
That must be why task manager shows multiple examples of chrome.exe under processes. I wondered about that.