If this The Phoenix review of the upcoming game "Bioshock" is any indication, then the game is certainly not based on Ayn Rand's philosophy of Objectivism, or on Atlas Shrugged. Here are some quotes that justify that comment.
According to BioShock’s foundation myth, Ryan envisioned his sub-aquatic metropolis (inspired by Ayn Rand, and especially Atlas Shrugged) as the place where man could realize his potential, unfettered by the restrictions placed upon him by government and religion. He populated the city with the greatest minds the world had to offer: industrialists, doctors, artists. Rapture had room only for the productive; there was no place for the weak, the infirm, or even the mediocre commoners that Ryan considered a drain on society.
Objectivism does not suppose that a society could function without government--there has to be some entity that can protect individual rights, which is the fundamental principle upon with Objectivist politics is based. Second, Ayn Rand had nothing against "the mediocre commoners," insofar as the typical person was as productive as his or her abilities made possible and to the extent that any person did not live life as a parasite upon the more productive. And so, from the beginning, the game's premises are perversions of Objectivism, not examples of it.
What you learn pretty quickly is that the first fissure in Ryan’s master plan opened with the discovery of an element called ADAM, which allowed for genetic modification far beyond the bounds of medical science. Freed from any ethical constraints, the people of Rapture set about developing strange and perverse abilities for themselves.
Notice that part, "freed from any ethical constraints." It's an implication that Objectivism has no ethics that would guide individuals in such a situation. Of course, Objectivism does have such an ethics, and it would result in individuals making the most rational long-term decisions possible--meaning, an Objectivist would be the last person to undergo a genetic modification without considering the possible effects. Then again, it's interesting that "developing strange and perverse abilities" is, according to the review, primarily an ethical question.
And yet, the freedom given the player is also subverted to give the game its greatest resonance: if the free will of one diminishes that of another, are they not both slaves? Andrew Ryan dreamed of a city where the great would not be constrained by the small; Rapture failed because he didn’t understand that the great rely on the small. As one character says, Ryan brought people to Rapture to be captains of industry, but they still needed someone to clean the toilets.
Again, although Objectivism does exalt the greatness of mankind, and therefore holds particular respect for those who utilize their abilities to the fullest, it does not conversely consider those without such abilities to be inferior. All Objectivism demands, morally, is that each individual strive for the highest that he can achieve, whether he's a brain surgeon or a janitor.
Objectivism in no way assumes that "the great (are) constrained by the small," except to the extent that government links a chain between them and makes slaves of the productive for the non-productive. If this review is correct, then "Bioshock" is a horrible rendition of Objectivism that will do nothing but perpetuate the negative stereotypes held by those who understand very little about the philosophy.