One of the comments in the link I said suggested FDev had to hand craft the Sol system obviously so it represents what we know today but in 3303. Its one of the disappointing reasons the Earth texture is lower quality than some of the procedural generated ELWs. The other systems are easy because its all just procedural. Sol takes effort and man hours.
I was disappointed to learn Mars was terraformed. I wanted to SRV around on the red planet. So the moon and probably Triton would be highly developed in 3303 and potentially one gigantic city and its probably akin to doing "atmospheric" planets, the amount of work that would be required. My gut feeling is they probably will never get done. I hope I am wrong and they do some great locations. I will however believe it when I see it.
Edit: I am sorry to say I have been to Sol once, and that's it. I meant to go back to get photos of Earth when Europe is in daylight but never did.. (yet). The Earth texture is pretty disappointing from a fidelity point of view.