How MINIMCOM and OMCOM swapped roles

In the beginning, OMCOM was a supercomputer who had a personality module and nobody to interact with. Rome was the Vuduri he cared about the most. In fact, he thought of her as his mother since she created him and finished his construction. But Rome was part of the Overmind and really did not have the skill set to interact with OMCOM in a meaningful way.

Then Rei came along. He was quirky, undisciplined, brilliant and engaging. OMCOM took to him right from the start because unlike the Vuduri, he treated OMCOM as a genuine entity instead of an appliance. After Rei and Rome slept together, OMCOM engineered Rome being cast out, Cesdiud, so that she could be freed of the cultural (and legal) restriction of arming memrons with Casimir Pumps.

Once the VIRUS units were developed and OMCOM transferred his consciousness to the gigantic mass and became Planet OMCOM, he became more distant, more god-like and we will not find out what he was doing out there until The Milk Run. MINIMCOM, on the other hand, was an effete, prissy little autopilot computer without access to emotions or even a personality module. In order for MINIMCOM to complete his mission of shepherding the Ark II to Deucado, he was augmented with uncounted peta-bytes of memory and processors and acquired a bit of OMCOM's personality in the process.

The only thing you can say is that MINIMCOM evolved. He had the processing power of OMCOM and a responsibility for seeing to it that Rei, Rome and the Ark II reached its target. MINIMCOM became caring. At first, he hid it behind an acerbic personality and often times had trouble hiding his sarcastic responses to human foibles. But when the time came, he sacrificed himself so that his charges could survive the crash-landing on Deucado.

He did not die. He rebuilt himself by infusing his memrons within the airframe of his space tug and became a starship. He developed a genuine affection for Rei, Rome and other humans to the point where they considered him a member of the family. He was so dedicated and industrious that he was emancipated and no longer required to serve humans. It was far too late, though. He loved Rei and Rome and even admitted so when he thought he was going to die during The Ark Lords crisis. He even gave "birth" to a son named Junior who figures to some degree in The Ark Lords and to a greater degree in subsequent novels.

OMCOM returned, or at least a clone of him, in The Ark Lords and was an effete, somewhat sarcastic, mostly humorless, servant computer dedicated to navigating Rome's archives.

In the new novel Rome's Evolution, you will see MINIMCOM acquire new capabilities and really push his interactions with humans to a whole new level. OMCOM's clone becomes somewhat animated but his entire persona resembles that of the early MINIMCOM.

Bottom line: OMCOM became infinite and removed himself from day to day interactions with humans as an equal. MINIMCOM was given the capability to interact and did so to the best of his abilities. Many people consider MINIMCOM their absolute favorite character.

Go figure.