Tetsujin 28

Was browsing throught some youtube videos when i came across this. a teaser trailer of a movie film by IMAGI, Tetsujin 28 i wonder if It's the first manga to feature a giant robot and maybe the first to start the whole mecha love in manga and anime. is it? heres the offical website
http://www.imagi.com.hk/t28/web/index.php