Peikoff is known as Rand's "legal and intellectual heir." I daresay that the "legal heir" part provides more of an income, but that's just me being snarky. I do have some reasons for the snark, so we'll get those out of the way first.
Ayn Rand was a novelist, not an economist, not a psychologist, not a political scientist, and not a philosopher. Of that list, the one closest to the work of a novelist is psychologist, as both study people in an analytical way. That might explain, to a certain extent, her relationship with Nathaniel Branden, the intellectual part of it, anyway.
But Rand had her coterie, "The Collective" as they called themselves, with what they thought was irony. And, indeed, there was irony there, just not the sort that they thought. In The Collective there were psychologists, political scientists, economists, and philosophers. I'll also give various devils their due and note that, in several cases, for example, Alan Greenspan, the economic ideas were not utterly loony, just largely untested. Monetarism (from Milton Friedman, who had his own cultish thing going with the Chicago School of economics) looked like an idea worth testing, all the way until the early 1980s, when it was tested, and found to be lacking. It turned out that you couldn't actually control the money supply very easily, and there was too much in the way of other factors (monetary velocity, "pseudo-money," like stock being used in mergers, etc.) to make the "money supply" into a control knob for inflation. Greenspan, being a pragmatic fellow, did not try monetarism again when he became Fed Chairman.
Leonard Peikoff was the academic philosopher of the group, and I strongly suspect that the weaknesses in Rand's philosophical positions grew out of Peikoff's failings. I read one of his articles in The Objectivist, "The Analytic-Synthetic Dichotomy" (May 1967), and it was clear to me at the ripe age of 17 that he was an intellectual lightweight. His argument first mischaracterized the epistemological principle that he was describing, and then, because that mischaracterization resulted in moral and ethical conclusions that he found abhorrent, decided that the underlying philosophy was wrong.
However, this was one of Rand's favorite techniques of argumentation, so Peikoff and Rand got along swimmingly, would be my guess. I'll also hypothesize (not a very risky leap, this) that he idolized her, and she liked being idolized.
So Peikoff wound up being, more-or-less, the last man standing from The Collective, a sure friend to a lonely, depressed woman in her later years, and, having slammed him for being intellectually shallow, I shall not compound the criticism by impugning his other motives in any way. I'll even say outright that I don't think he was in it for the money, as it were, nor even the career advancement. I expect that he genuinely admired her and was standing by a friend.
Besides, what I'm about to quote is as good a job of channeling Rand as I think could be done:
The survival of this country will not be determined by the degree to which the government, simply by inertia, imposes taxes, entitlements, controls, etc., although such impositions will be harmful (and all of them and worse will be embraced or pioneered by conservatives, as Bush has shown). What does determine the survival of this country is not political concretes, but fundamental philosophy. And in this area the only real threat to the country now, the only political evil comparable to or even greater than the threat once posed by Soviet Communism, is religion and the Party which is its home and sponsor.
The most urgent political task now is to topple the Republicans from power, if possible in the House and the Senate. This entails voting consistently Democratic, even if the opponent is a "good" Republican.
In my judgment, anyone who votes Republican or abstains from voting in this election has no understanding of the practical role of philosophy in man's actual life, which means that he does not understand the philosophy of Objectivism, except perhaps as a rationalistic system detached from the world.
If you hate the Left so much that you feel more comfortable with the Right, you are unwittingly helping to push the U.S. toward disaster, i.e., theocracy, not in 50 years, but, frighteningly, much sooner.
The above statement may be reproduced or disseminated at will, without any requirement to consult or inform Dr. Peikoff.
– Leonard Peikoff, October 19, 2006