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I agree that your question is legitimate, and calling what Comcast did censorship does muddy the water, no doubt about it. Still, the link to the fired on-air guy really serves only to demonstrate Comcast's intent, which is to prevent, to the extent that it can, public discussion of topics which its owners would prefer weren't discussed. Glenn is describing the problem, not the solution. As such, his description is valid even without the details you're inquiring about.
Remedies are another matter. None seem to exist at the moment, largely because the public isn't engaged. Glenn is trying to engage the public. Isn't it incumbent on us, who presumably also see the problem, to suggest solutions? It seems like a job for all us good and true UT commenters to me....