Oh, and can someone please, explain to me, why Martha teleported herself back to Earth, right in the middle of all the slaughter??

Me too! I asked my friend about that today and apparently if she stayed on the ship there was nothing she could do to help stop what was happening but if she teleported back to Earth she might be able to get help (what sort of help I don't know) so that's what she did, and it had to be here cos jack was still to weak to teleport after being shot.

I suppose that kinda makes sense but nuh, why didn't she take the other two with her?

I don't think it made much sense. So maybe I just wasn't watching properly :)