The Obsolete Man makes quite an obvious comment on the role of government and certain ways in which powers can be abused or societies can go astray. The totalitarian state portrayed in the film gleefully broadcasts the executions of undesirables (1300 in 6 hours one time, if I remember correctly) such as, in the case we get to see, a man who has committed the mortal sin of being a librarian. The theme of publicly executing undesirables, by the way, bears amazing resemblance to the brutal regime of Mao Tse-tung, which was at it's heyday when this episode first aired.
At any rate, we already know that burning books is bad and I don't know that we need an entire twilight zone episode to show us that the next step of killing librarians is also bad, but it's an entertaining enough episode.
A lot of other IMDb users have complained that this episode is preachy, and I agree to a certain extent, but I also think that any film or story or TV show that shows the dangers of government can't be all bad, particularly given the astonishing political banditry that we have witnessed in America for the last 8 years. It's sad but unsurprising to me that the American economy is in shambles right now.
My favorite thing that the episode does is that it presents this quiet, unassuming man who lives a quiet life as a librarian, and even after his death sentence, he manages to completely undo the man who condemned him, and in front of a widespread audience as well. He uses the machine's rules against it and makes an incredibly powerful statement about political responsibility and the rights and wrongs of governmental power.
Pretty deep and intense material, and not the most fun I've had watching the twilight zone, but it's relevance can most certainly be felt today...