10 base food production instead of 5. I think there are other bonuses as well. I think I heard that it doesn't actually work properly though.

You don't really 'choose' a planet, you just name it. I believe the planet-selecting process is somewhat random, with basic parameters like 'Class 10' or whatever.

They work on your homeworld, they just don't work for the moving your homeworld button. Right? Which I don't think you should be able to do anyway, it doesn't make any sense.

Well, if you think of your homeworld more in terms of the capitol city of a nation then being able to change your capitol makes a lot of sense in certain situations.

However, I must admit that "homeworld" is not the best term for this. Maybe they should make the "homeworld" have a loyalty bonus (since it is only natural for its citizens to be more loyal to the civilization it spawned) and have also have a "capitol world" which receives the bonuses that the homeworld in the current version of the game, but can be moved to a different planet.

Yes, I like Sir Arfs a Lot's idea too! I never change my homeworld because it just doesn't seem real to do so (playing as human). To me, there can be no homeworld but Earth! Despite that, I wished I could move my capital to some of my better and more central planets... On the same token, it'd be nice if they made the bonus of having a capital more significant. Kind of like Civ4, where the more central the capital, the better for your empire (less penalty to economy).