How big is Earth?

[Suicide Junkie]

If you're counting gas giants on the same scale, we should be small or perhaps the low end of medium.

In terms of just rock worlds, low end of Large or high end of medium.

This one would be the high end of huge for rock:
http://www.cnn.com/2004/TECH/space/0...net/index.html

Population scales are completely out of proportion; on a gas giant like Jupiter, you could have two trillion people at Earth's population density. Also presuming that you don't take advantage of living at different altitudes for gobs more available space.

[Fyron]

The sizes and spaces are arbitrary and not meant to reflect reality in any way.

[geoschmo]

I always figured Earth as a Medium rock oxygen world because one of the medium Rock oxygen pics looks very much like a small picture of earth.

[Black_Knyght]

I always assume Earth as a baseline - Rock, Oxygen, Medium

This simplifies references to me for other types of planets