There will be the option of building colonies in Infinity. These will vary from a tiny mining camp to a sprawling trading city. All of these are player-run (excluding the cores, as they are computer-run), meaning you can make any colony you want. The more players that work together or bigger the IPO, the better the colony is, as this is a large feat to accomplish.
There isn't much detail about colonies so far, but it is widely believed that there should be a 'Happiness' portion of the colony, meaning if it is unhappy everyone will leave; likewise, if it is a happy colony it will have loads of settlers settling there.
It is widely believed that settlers will come if the environment of the planet can support life comfortably, if there are enough jobs, and even distance from the cores or nearby colonised world.
Colonies will need a power supply and a food/resource demand as well, meaning the maker of the colony will need to supply them. This is to encourage people working together or IPOs to work together to form colonies.
Here is what a colony could look like http://www.infinity-universe.com/Infinity/index.php?option=com_zoom&Itemid=82&catid=9.
Here is a rough list of what buildings might be at launch (as well as all contributions).