“The carefully limited measures that Comcast takes to manage traffic on its broadband network are a reasonable part of Comcast’s strategy to ensure a high-quality, reliable Internet experience for all Comcast High-Speed Internet customers and are used by many other ISPs around the world.”
At issue is the definition of "reasonable network management", a term the FCC introduced in a 2005 policy statement. Comcast's recent upgrades to end-user modems installs a product named "PowerBoost" which offers bursts of speed at the beginning of a download. This helps improve load times for small images and the send/receive process for emails but does little for streaming video, voice calls or peer-2-peer communication protocols that rely on a continuous uninterrupted stream of data.
Here is comcast's response to the FCC ruling:
Read this document on Scribd: Comcast Response to Further FP ex parte