From the FCC's Broadband.Gov site:
The American Recovery and Reinvestment Act of 2009 (Recovery Act) was signed into law on February 17, 2009. The Broadband Initiatives funded in the Act are intended to accelerate broadband deployment across the United States. The Recovery Act authorizes the FCC to create a National Broadband Plan, that “shall seek to ensure that all people of the United States have access to broadband capability and shall establish benchmarks for meeting that goal.”
The FCC is gathering information from broadband users to see what their connection speeds actually are. I decided to try it out. The next two charts reflect the speed I got from using Internet Explorer 7 on Windows XP running in a virtual instance on my iMac. There are two possible testing scenarios. One uses Ookla and the other uses M-Lab. The first tester is randomly selected and you are offered the chance to test again using the other, which I did. BTW, I'm a Comcast customer.
These two charts reflect the results I got using Safari on the iMac.
I wonder why the results differ so widely between M-Lab and Ookla.