A proper official site, finally!
It is the only proper official site I'm aware of for TTW (Facebook etc doesn't count of course!). Great design, gallery, info, supporting quotes from some artists and academics* and more ..
The only catch (if you don't speak Japanese), is that it is in Japanese!
http://tothewonder.jp/
Japanese poster is pretty cool too:
http://www.impawards.com/2013/to_the_wonder_ver11_xlg.html
And trailer is a bit different, especially in the music choices
http://youtu.be/qeYia-F6sBo
*Google translated
http://translate.google.com/translate?sl=ja&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Ftothewonder.jp%2Fcomment%2Findex.html&act=url