I have an interesting screenshot from a recent test in multiplayer. Unfortunately, my web hoster won't let me in for some reason so I'll try to describe what I saw.
15 turns into the game, playing as the Eoladi, my scout explores an unknown system and I realize it is mark as an outpost of my race. There was no message in the Sitrep about finding a colony, the planet has no specials at all, yet there are 37 people of my race on it. Checking my planets around, I notice my home system also got a free outpost with 180 people on it.
At this point in the game, I control 3 planets and have built a single system colony ship. I turned on migration a couple of turns ago to boost my newly establish colonies both in system and out of system. I am almost positive there was no Eoladi on the fifth planet in my system at that time, when I marked it for a colony ship I would have noticed it.
So I guess the AI is still not cheating
I wonder how many races have this ability.