Kepler data yields Earth-mass 'gas giant'

Depends on the size of the observer! :)

Re: Proto-planet

A solar system is never done forming, but will continue "clumping together" as long as it's sun is "alive" and long after. There however a few things that will happen that makes part of it more or less stable, and that is mostly planets. Among other things what makes a planet a planet, as per the new definition, is that it has cleared the neighbourhood. In a three-body system, that is system with three bodies of significant mass, and where the mass of one is so big that the last two orbits it, the two orbiting bodies can't be in the same orbit. If their orbits are too close their gravitational pull on each other each time they pass each other either throw both into new orbits or into each other, thus "clearing the neighbourhood". This of course will take a while, and it will take greater and greater time the further out the orbit is. So way out there in what we call the Oort cloud around our star the system is still forming to a degree, but the orbital periods are so long that in fact it might never happen and the gravitational pull from other stars might throw it out of whack. Close to our star though, this is nearly done. We have some debris left over between Mars and Jupiter and a few other places, but mostly it is cleared for stuff.

The planet they are talking about here though has an orbital period of 22 days. That means that if you throw in another body in it's orbit and try to balance it perfectly to avoid collision then you would still probably achieve it within in a year regardless. It had most likely finished forming long before it's host star ignited.