[Joachim]

Despite all the strategy guides saying that you should not play icy planets, I for one like to. Just one of those wierd preference things I guess.

As for PBW advantage - that seems to be the case of most not taking and thus you can trade the tech at a premium. Of course this can be a little rock-paper-scissors at times....
Or like in a current game you choose Ice/Methane (cause the deep bluey/purple is pretty!)and discover that your nearest negihbour is also Ice/Methane and you are both trapped in a small cluster by another player.....

Lets not forget the roleplaying as well - do you play a race from a very cold, dark world differently to the squishy gas giant or hard rock planet?

Joachim.