My mate just posted info on his fb profile that The Mysterious Cities of Gold is coming to Wii U & 3DS. Developed by Neko Entertainment. Never heard of them but damn I so excited for the game! The original anime series was one of my favorite when I was a kid... which makes me realise how old I am now!
The whole series was about one bigger than life adventure giving great sense wander - that sense we had playing 16 bit action adventure games, or even recently latest entries in zelda franchise and to a smaller degree games like Skyrim or first Assassins Creed.
Apparently series has been reviewed recently. That would answer the question why the game is being in development now. The original looks very dated now, with cheesy intro song ( although really catchy ), but I'm 100% sure anyone would still find an enjoyment in it. As for the game now much is known yet.
Source Children Of The Sun, Take Note: The Mysterious Cities of Gold Is Coming To Wii U And 3DS