Gary Kline, an ork, is the CEO of Horizon. And, most likely, their first experiment in data washing. In other words, creating a persona whole-cloth with background (including trid features and newsfeed articles) and all that is so convincing everyone buys into it.
However, I've been thinking, and if Deus is still around, he most likely has changed his code (and icon, obviously) enough so that he won't be recognized by the people who VERY MUCH want to see him dead. I see him as the Magneto type of villain. When he was a young proto-AI, Renraku did the equivalent of putting a kink bomb in his head, by putting a manual kill-code on his hardware. The justifiable feeling of hurt and betrayal is what awoke Deus to sentience. The Arcology shutdown was all for the purpose of helping him escape captivity. Problem is, people knew he escaped, which meant he had to fight off people who wanted him dead. After that, his goal shifted to gaining enough power to prevent anyone from being able to capture or threaten him in that way ever again. Which is why he showed up on the ECSE during the Novatech IPO.
Now, if he survived the Crash, and everyone believed him dead, he was free of his largest concern. Now, AIs can spoof their codebase to change their access ID. It takes time, but they can do it, meaning that, if he used a new icon as well, then he could pass undetected, especially with the rash of new AIs taking root in the Matrix. This means that he can pursue his agenda covertly, without interference.
Of course, the corps now know that AIs are out there, and are actively hunting them down, either to kill or to study and control. So who better than one of the original AIs to gather followers, and take up the call of AI rights? And what better vehicle to use for that campaign than one of the most powerful (if not THE most powerful) media corps in the world? He's already seen that direct action has limited benefits, especially compared to the consequences it caused him. So why not try a new tact?
So, after gathering some digital followers, he makes contact with Horizon, and, not seeming like his old self, no one suspects his true nature as he helps the "friendly" megacorp get on the right side of the AI/Technomancer issue, helping his 'people', and solidifying a place for himself in the Post-Crash Matrix.
It takes a great deal of prowess and power to simultaneously hack and broadcast a message to every single device in the world. Of course, the idea wasn't new. Lugh Surehand did it using untold wealth and a series of dedicated satellites that spammed the airwaves, but the leadup to the announcement of the Land of Promise was long, and required a great deal of planning. To do it on a shorter timetable, without lifting dedicated satellites into space, from a variety of megas as Surehand did, would require a great deal of power and skill, most likely the power that only one of the most powerful AIs could bring to bear.
That's right, Pulsar is Deus.
