I'm pretty sure this stacks up the modifications to your various stats that you accrue through these decisions as well, though I'm not entirely sure. This also leads to multiple entries in the end-game colony text summary, like say if you choose communal decision making the first time and elections the second time, both will be in the text summary - v0.2.71
To replicate, select a planet and set down the colony, and while making decisions on it (like for instance, on education policy), click on LOG in the lower part of the screen, then try and go back to managing the colony. You will be back on planet selection.