Wow, the competition among open source browsers is getting so heated that you have to stay on top of the day-to-day goings on with the pre-release versions. We've written before about Google Chrome winning speed tests, and I keep hearing people cite it as the fastest browser. Meanwhile, CNet has been posting speed results showing very strong performance from the beta version of Firefox 3.1 (it is indeed snappy).? Now, there are some new performance results out that show the nightly builds of Webkit--the open source rendering engine within Safari and Chrome--posting the fastest speeds of all.